diff --git a/client/src/components/categorical/categorical.js b/client/src/components/categorical/categorical.js
index c8f4ae4e1..25d4646cb 100644
--- a/client/src/components/categorical/categorical.js
+++ b/client/src/components/categorical/categorical.js
@@ -5,34 +5,13 @@ import { connect } from "react-redux";
 import * as globals from "../../globals";
 import Category from "./category";
 
-/* Cap the max number of displayed categories */
-const truncateCategories = options => {
-  const numOptions = _.size(options);
-  if (numOptions <= globals.maxCategoricalOptionsToDisplay) {
-    return options;
-  }
-  return _(options)
-    .map((v, k) => ({ name: k, val: v }))
-    .sortBy("val")
-    .slice(numOptions - globals.maxCategoricalOptionsToDisplay)
-    .transform((r, v) => {
-      r[v.name] = v.val;
-    }, {})
-    .value();
-};
-
 @connect(state => ({
-  ranges: _.get(state.controls.world, "summary.obs", null),
-  categorySelectionLimit: _.get(
-    state.config,
-    "parameters.max-category-items",
-    globals.configDefaults.parameters["max-category-items"]
-  )
+  categoricalSelectionState: state.controls.categoricalSelectionState
 }))
 class Categories extends React.Component {
   render() {
-    const { ranges, categorySelectionLimit } = this.props;
-    if (!ranges) return null;
+    const { categoricalSelectionState } = this.props;
+    if (!categoricalSelectionState) return null;
 
     return (
       <div
@@ -47,27 +26,9 @@ class Categories extends React.Component {
         >
           Categorical Metadata
         </p>
-        {_.map(ranges, (value, key) => {
-          const isColorField = key.includes("color") || key.includes("Color");
-          const isSelectableCategory =
-            value.options &&
-            !isColorField &&
-            key !== "name" &&
-            value.numOptions < categorySelectionLimit;
-
-          if (isSelectableCategory) {
-            const categoryOptions = truncateCategories(value.options);
-            return (
-              <Category
-                key={key}
-                metadataField={key}
-                values={categoryOptions}
-                isTruncated={categoryOptions !== value.options}
-              />
-            );
-          }
-          return undefined;
-        })}
+        {_.map(categoricalSelectionState, (catState, catName) => (
+          <Category key={catName} metadataField={catName} />
+        ))}
       </div>
     );
   }
diff --git a/client/src/components/categorical/category.js b/client/src/components/categorical/category.js
index 41b05a361..3c1cebb41 100644
--- a/client/src/components/categorical/category.js
+++ b/client/src/components/categorical/category.js
@@ -2,29 +2,15 @@ import React from "react";
 import _ from "lodash";
 import { connect } from "react-redux";
 import { FaChevronRight, FaChevronDown } from "react-icons/fa";
-import memoize from "memoize-one";
-import { Button, Tooltip, Position } from "@blueprintjs/core";
+import { Button, Tooltip } from "@blueprintjs/core";
 
 import * as globals from "../../globals";
 import Value from "./value";
 import alphabeticallySortedValues from "./util";
 
-const countCategories = (values, optsAsBools) =>
-  _.reduce(
-    values,
-    (r, v, k) => {
-      r.total += 1;
-      if (optsAsBools[k]) {
-        r.on += 1;
-      }
-      return r;
-    },
-    { total: 0, on: 0 }
-  );
-
 @connect(state => ({
   colorAccessor: state.controls.colorAccessor,
-  categoricalAsBooleansMap: state.controls.categoricalAsBooleansMap
+  categoricalSelectionState: state.controls.categoricalSelectionState
 }))
 class Category extends React.Component {
   constructor(props) {
@@ -33,24 +19,30 @@ class Category extends React.Component {
       isChecked: true,
       isExpanded: false
     };
-    this.countCategories = memoize((values, optsAsBools) =>
-      countCategories(values, optsAsBools)
-    );
   }
 
   componentDidUpdate() {
-    const { categoricalAsBooleansMap, metadataField, values } = this.props;
-    const categoryCount = this.countCategories(
-      values,
-      categoricalAsBooleansMap[metadataField]
-    );
-    if (categoryCount.on === categoryCount.total) {
+    const { categoricalSelectionState, metadataField } = this.props;
+    const cat = categoricalSelectionState[metadataField];
+    const categoryCount = {
+      // total number of options in this category
+      totalOptionCount: cat.numOptions,
+      // number of selected options in this category
+      selectedOptionCount: _.reduce(
+        cat.optionSelected,
+        (res, cond) => (cond ? res + 1 : res),
+        0
+      )
+    };
+    if (categoryCount.selectedOptionCount === categoryCount.totalOptionCount) {
       /* everything is on, so not indeterminate */
       this.checkbox.indeterminate = false;
-    } else if (categoryCount.on === 0) {
+    } else if (categoryCount.selectedOptionCount === 0) {
       /* nothing is on, so no */
       this.checkbox.indeterminate = false;
-    } else if (categoryCount.on < categoryCount.total) {
+    } else if (
+      categoryCount.selectedOptionCount < categoryCount.totalOptionCount
+    ) {
       /* to be explicit... */
       this.checkbox.indeterminate = true;
     }
@@ -74,11 +66,10 @@ class Category extends React.Component {
   }
 
   toggleNone() {
-    const { dispatch, metadataField, value } = this.props;
+    const { dispatch, metadataField } = this.props;
     dispatch({
       type: "categorical metadata filter none of these",
-      metadataField,
-      value
+      metadataField
     });
     this.setState({ isChecked: false });
   }
@@ -94,13 +85,15 @@ class Category extends React.Component {
   }
 
   renderCategoryItems() {
-    const { values, metadataField } = this.props;
-    return _.map(alphabeticallySortedValues(values), (v, i) => (
+    const { categoricalSelectionState, metadataField } = this.props;
+
+    const cat = categoricalSelectionState[metadataField];
+    const optTuples = alphabeticallySortedValues([...cat.optionIndex]);
+    return _.map(optTuples, (tuple, i) => (
       <Value
-        key={v}
+        key={tuple[1]}
         metadataField={metadataField}
-        count={values[v]}
-        value={v}
+        optionIndex={tuple[1]}
         i={i}
       />
     ));
@@ -108,12 +101,15 @@ class Category extends React.Component {
 
   render() {
     const { isExpanded, isChecked } = this.state;
-    const { metadataField, colorAccessor, isTruncated } = this.props;
+    const {
+      metadataField,
+      colorAccessor,
+      categoricalSelectionState
+    } = this.props;
+    const { isTruncated } = categoricalSelectionState[metadataField];
     return (
       <div
         style={{
-          // display: "flex",
-          // alignItems: "baseline",
           maxWidth: globals.maxControlsWidth
         }}
       >
diff --git a/client/src/components/categorical/util.js b/client/src/components/categorical/util.js
index 1f1dfd4a3..58707776c 100644
--- a/client/src/components/categorical/util.js
+++ b/client/src/components/categorical/util.js
@@ -1,7 +1,11 @@
 // jshint esversion: 6
+
+// values is [ [optVal, optIdx], ...]
+// index is range array
+// return sorted index
 export default values =>
-  Object.keys(values).sort((a, b) => {
-    const textA = a.toUpperCase();
-    const textB = b.toUpperCase();
+  values.sort((a, b) => {
+    const textA = String(a[0]).toUpperCase();
+    const textB = String(b[0]).toUpperCase();
     return textA < textB ? -1 : textA > textB ? 1 : 0;
   });
diff --git a/client/src/components/categorical/value.js b/client/src/components/categorical/value.js
index 09e47fc11..f2a1afb82 100644
--- a/client/src/components/categorical/value.js
+++ b/client/src/components/categorical/value.js
@@ -4,45 +4,49 @@ import React from "react";
 import _ from "lodash";
 
 @connect(state => ({
-  categoricalAsBooleansMap: state.controls.categoricalAsBooleansMap,
+  categoricalSelectionState: state.controls.categoricalSelectionState,
   colorScale: state.controls.colorScale,
   colorAccessor: state.controls.colorAccessor,
   schema: _.get(state.controls.world, "schema", null)
 }))
 class CategoryValue extends React.Component {
   toggleOff() {
-    const { dispatch, metadataField, value } = this.props;
+    const { dispatch, metadataField, optionIndex } = this.props;
     dispatch({
       type: "categorical metadata filter deselect",
       metadataField,
-      value
+      optionIndex
     });
   }
 
   toggleOn() {
-    const { dispatch, metadataField, value } = this.props;
+    const { dispatch, metadataField, optionIndex } = this.props;
     dispatch({
       type: "categorical metadata filter select",
       metadataField,
-      value
+      optionIndex
     });
   }
 
   render() {
     const {
-      categoricalAsBooleansMap,
+      categoricalSelectionState,
       metadataField,
-      count,
-      value,
+      optionIndex,
       colorAccessor,
       colorScale,
       i,
       schema
     } = this.props;
 
-    if (!categoricalAsBooleansMap) return null;
+    if (!categoricalSelectionState) return null;
+
+    const category = categoricalSelectionState[metadataField];
+    const selected = category.optionSelected[optionIndex];
+    const count = category.optionCount[optionIndex];
+    const value = category.optionValue[optionIndex];
+    const displayString = String(category.optionValue[optionIndex]).valueOf();
 
-    const selected = categoricalAsBooleansMap[metadataField][value];
     /* this is the color scale, so add swatches below */
     const c = metadataField === colorAccessor;
     let categories = null;
@@ -78,7 +82,7 @@ class CategoryValue extends React.Component {
               type="checkbox"
             />
             <span className="bp3-control-indicator" />
-            {value}
+            {displayString}
           </label>
         </div>
         <span>
diff --git a/client/src/reducers/controls.js b/client/src/reducers/controls.js
index 09d9b79c4..81eac6712 100644
--- a/client/src/reducers/controls.js
+++ b/client/src/reducers/controls.js
@@ -12,34 +12,109 @@ import {
   diffexpDimensionName,
   makeContinuousDimensionName
 } from "../util/nameCreators";
+import { fillRange } from "../util/typedCrossfilter/util";
+
+/*
+Selection state for categoricals are tracked in an Object that
+has two main components for each category:
+1. mapping of option value to an index
+2. array of bool selection state by index
+Remember that option values can be ANY js type, except undefined/null.
+
+  {
+    _category_name_1: {
+      // map of option value to index
+      optionIndex: Map([
+        optval1: index,
+        ...
+      ])
+
+      // index->selection true/false state
+      optionSelected: [ true/false, true/false, ... ]
+
+      // number of options
+      numOptions: number,
+
+      // isTruncated - true if the options for selection has
+      // been truncated (ie, was too large to implement)
+    }
+  }
+*/
+function topNoptions(summary) {
+  const counts = _.map(summary.categories, cat => summary.options[cat]);
+  const sortIndex = fillRange(new Array(summary.numOptions)).sort(
+    (a, b) => counts[b] - counts[a]
+  );
+  const sortedCategories = _.map(sortIndex, i => summary.categories[i]);
+  const sortedCounts = _.map(sortIndex, i => counts[i]);
+  const N = globals.maxCategoricalOptionsToDisplay;
+
+  if (sortedCategories.length < N) {
+    return [sortedCategories, sortedCounts];
+  }
+  return [sortedCategories.slice(0, N), sortedCounts.slice(0, N)];
+}
 
-function createCategoricalAsBooleansMap(world) {
+function createCategoricalSelectionState(state, world) {
   const res = {};
-  _.each(world.summary.obs, (value, key) => {
-    if (value.options && key !== "name") {
-      const optionsAsBooleans = {};
-      _.each(value.options, (_value, _key) => {
-        optionsAsBooleans[_key] = true;
-      });
-      res[key] = optionsAsBooleans;
+  _.forEach(world.summary.obs, (value, key) => {
+    if (value.categories) {
+      const isColorField = key.includes("color") || key.includes("Color");
+      const isSelectableCategory =
+        !isColorField &&
+        key !== "name" &&
+        value.categories.length < state.maxCategoryItems;
+      if (isSelectableCategory) {
+        const [optionValue, optionCount] = topNoptions(value);
+        // const optionCount = Object.values(value.options);
+
+        const optionIndex = new Map(optionValue.map((v, i) => [v, i]));
+        const numOptions = optionIndex.size;
+        const optionSelected = new Array(numOptions).fill(true);
+        const isTruncated = optionValue.length < value.numOptions;
+        res[key] = {
+          optionValue, // array: of natively typed option values
+          optionIndex, // map: option value (native type) -> option index
+          optionSelected, // array: t/f selection state
+          numOptions, // number: of options
+          isTruncated, // bool: true if list was truncated
+          optionCount // array: cardinality of each option
+        };
+      }
     }
   });
   return res;
 }
 
+/*
+given a categoricalSelectionState, return the list of all option values
+where selection state is true (ie, they are selected).
+*/
+function selectedValuesForCategory(categorySelectionState) {
+  const selectedValues = _([...categorySelectionState.optionIndex])
+    .filter(tuple => categorySelectionState.optionSelected[tuple[1]])
+    .map(tuple => tuple[0])
+    .value();
+  return selectedValues;
+}
+
 const Controls = (
   state = {
     // data loading flag
     loading: false,
     error: null,
 
+    // configuration
+    maxCategoryItems: globals.configDefaults.parameters["max-category-items"],
+
+    // the whole big bang
     universe: null,
 
     // all of the data + selection state
     world: null,
     colorName: null,
     colorRGB: null,
-    categoricalAsBooleansMap: null,
+    categoricalSelectionState: null,
     crossfilter: null,
     dimensionMap: null,
     userDefinedGenes: [],
@@ -72,6 +147,17 @@ const Controls = (
           Initialization, World/Universe management
           and data loading.
     ******************************************************/
+    case "configuration load complete": {
+      // there are a couple of configuration items we need to retain
+      return {
+        ...state,
+        maxCategoryItems: _.get(
+          state.config,
+          "parameters.max-category-items",
+          globals.configDefaults.parameters["max-category-items"]
+        )
+      };
+    }
     case "initial data load start": {
       return { ...state, loading: true };
     }
@@ -83,7 +169,10 @@ const Controls = (
       const world = World.createWorldFromEntireUniverse(universe);
       const colorName = new Array(universe.nObs).fill(globals.defaultCellColor);
       const colorRGB = _.map(colorName, c => parseRGB(c));
-      const categoricalAsBooleansMap = createCategoricalAsBooleansMap(world);
+      const categoricalSelectionState = createCategoricalSelectionState(
+        state,
+        world
+      );
       const crossfilter = Crossfilter(world.obsAnnotations);
       const dimensionMap = World.createObsDimensionMap(crossfilter, world);
 
@@ -135,7 +224,7 @@ const Controls = (
         world,
         colorName,
         colorRGB,
-        categoricalAsBooleansMap,
+        categoricalSelectionState,
         crossfilter,
         dimensionMap,
         colorAccessor: null
@@ -152,7 +241,10 @@ const Controls = (
       );
       const colorName = new Array(world.nObs).fill(globals.defaultCellColor);
       const colorRGB = _.map(colorName, c => parseRGB(c));
-      const categoricalAsBooleansMap = createCategoricalAsBooleansMap(world);
+      const categoricalSelectionState = createCategoricalSelectionState(
+        state,
+        world
+      );
       const crossfilter = Crossfilter(world.obsAnnotations);
       const dimensionMap = World.createObsDimensionMap(crossfilter, world);
 
@@ -197,7 +289,7 @@ const Controls = (
         world,
         colorName,
         colorRGB,
-        categoricalAsBooleansMap,
+        categoricalSelectionState,
         crossfilter,
         dimensionMap,
         colorAccessor: null
@@ -422,83 +514,87 @@ const Controls = (
           Categorical metadata
     *******************************/
     case "categorical metadata filter select": {
-      const newCategoricalAsBooleansMap = {
-        ...state.categoricalAsBooleansMap,
+      const newOptionSelected = Array.from(
+        state.categoricalSelectionState[action.metadataField].optionSelected
+      );
+      newOptionSelected[action.optionIndex] = true;
+      const newCategoricalSelectionState = {
+        ...state.categoricalSelectionState,
         [action.metadataField]: {
-          ...state.categoricalAsBooleansMap[action.metadataField],
-          [action.value]: true
+          ...state.categoricalSelectionState[action.metadataField],
+          optionSelected: newOptionSelected
         }
       };
-      // update the filter for the one category that changed state
+
+      // update the filter to match all selected options
+      const cat = newCategoricalSelectionState[action.metadataField];
       state.dimensionMap[obsAnnoDimensionName(action.metadataField)].filterEnum(
-        _.filter(
-          _.map(
-            newCategoricalAsBooleansMap[action.metadataField],
-            (val, key) => (val ? key : false)
-          )
-        )
+        selectedValuesForCategory(cat)
       );
+
       return {
         ...state,
-        categoricalAsBooleansMap: newCategoricalAsBooleansMap
+        categoricalSelectionState: newCategoricalSelectionState
       };
     }
     case "categorical metadata filter deselect": {
-      const newCategoricalAsBooleansMap = {
-        ...state.categoricalAsBooleansMap,
+      const newOptionSelected = Array.from(
+        state.categoricalSelectionState[action.metadataField].optionSelected
+      );
+      newOptionSelected[action.optionIndex] = false;
+      const newCategoricalSelectionState = {
+        ...state.categoricalSelectionState,
         [action.metadataField]: {
-          ...state.categoricalAsBooleansMap[action.metadataField],
-          [action.value]: false
+          ...state.categoricalSelectionState[action.metadataField],
+          optionSelected: newOptionSelected
         }
       };
-      // update the filter for the one category that changed state
+
+      // update the filter to match all selected options
+      const cat = newCategoricalSelectionState[action.metadataField];
       state.dimensionMap[obsAnnoDimensionName(action.metadataField)].filterEnum(
-        _.filter(
-          _.map(
-            newCategoricalAsBooleansMap[action.metadataField],
-            (val, key) => (val ? key : false)
-          )
-        )
+        selectedValuesForCategory(cat)
       );
+
       return {
         ...state,
-        categoricalAsBooleansMap: newCategoricalAsBooleansMap
+        categoricalSelectionState: newCategoricalSelectionState
       };
     }
     case "categorical metadata filter none of these": {
-      const newCategoricalAsBooleansMap = {
-        ...state.categoricalAsBooleansMap
-      };
-      _.forEach(
-        newCategoricalAsBooleansMap[action.metadataField],
-        (v, k, c) => {
-          c[k] = false;
+      const newCategoricalSelectionState = {
+        ...state.categoricalSelectionState,
+        [action.metadataField]: {
+          ...state.categoricalSelectionState[action.metadataField],
+          optionSelected: Array.from(
+            state.categoricalSelectionState[action.metadataField].optionSelected
+          ).fill(false)
         }
-      );
+      };
       state.dimensionMap[
         obsAnnoDimensionName(action.metadataField)
       ].filterNone();
       return {
         ...state,
-        categoricalAsBooleansMap: newCategoricalAsBooleansMap
+        categoricalSelectionState: newCategoricalSelectionState
       };
     }
     case "categorical metadata filter all of these": {
-      const newCategoricalAsBooleansMap = {
-        ...state.categoricalAsBooleansMap
-      };
-      _.forEach(
-        newCategoricalAsBooleansMap[action.metadataField],
-        (v, k, c) => {
-          c[k] = true;
+      const newCategoricalSelectionState = {
+        ...state.categoricalSelectionState,
+        [action.metadataField]: {
+          ...state.categoricalSelectionState[action.metadataField],
+          optionSelected: Array.from(
+            state.categoricalSelectionState[action.metadataField].optionSelected
+          ).fill(true)
         }
-      );
+      };
       state.dimensionMap[
         obsAnnoDimensionName(action.metadataField)
       ].filterAll();
       return {
         ...state,
-        categoricalAsBooleansMap: newCategoricalAsBooleansMap
+        categoricalSelectionState: newCategoricalSelectionState
       };
     }
 
diff --git a/client/src/util/stateManager/summarizeAnnotations.js b/client/src/util/stateManager/summarizeAnnotations.js
index a17d85b16..734b0fe33 100644
--- a/client/src/util/stateManager/summarizeAnnotations.js
+++ b/client/src/util/stateManager/summarizeAnnotations.js
@@ -48,6 +48,12 @@ Example:
 
 NOTE: will not summarize the required 'name' annotation, as that is
 specified as unique per element.
+
+TODO: XXX - this data structure coerces all metadata categories into a string
+(ie, stores values as an Object property in the `options` field).   This looses
+information (eg, type) for category types which are not strings.  Consider an
+alterative data structure that does not use the object property for non-string
+data types (and does not use _.countBy to summarize).
 */
 function summarizeDimension(schema, annotations) {
   return _(schema)
@@ -58,11 +64,13 @@ function summarizeDimension(schema, annotations) {
       const continuous = type === "int32" || type === "float32";
 
       if (!continuous) {
+        const categories = _.uniq(_.flatMap(annotations, name));
         const options = _.countBy(annotations, name);
         const numOptions = _.size(options);
         return {
           numOptions,
-          options
+          options,
+          categories
         };
       }
 
diff --git a/client/src/util/stateManager/universe.js b/client/src/util/stateManager/universe.js
index a0999ef6a..69b1354b0 100644
--- a/client/src/util/stateManager/universe.js
+++ b/client/src/util/stateManager/universe.js
@@ -161,6 +161,32 @@ function RESTv02LayoutResponseToInternal(response) {
   return layout;
 }
 
+function reconcileSchemaCategoriesWithSummary(universe) {
+  /*
+  where we treat types as (essentially) categorical metadata, update
+  the schema with data-derived categories (in addition to those in
+  the server declared schema).
+
+  For example, boolean defined fields in the schema do not contain
+  explicit declaration of categories (nor do string fields).  In these
+  cases, add a 'categories' field to the schema so it is accessible.
+  */
+
+  _.forEach(universe.schema.annotations.obs, s => {
+    if (
+      s.type === "string" ||
+      s.type === "boolean" ||
+      s.type === "categorical"
+    ) {
+      const categories = _.union(
+        _.get(s, "categories", []),
+        _.get(universe.summary.obs[s.name], "categories", [])
+      );
+      s.categories = categories;
+    }
+  });
+}
+
 export function createUniverseFromRestV02Response(
   configResponse,
   schemaResponse,
@@ -199,6 +225,7 @@ export function createUniverseFromRestV02Response(
     universe.varAnnotations
   );
 
+  reconcileSchemaCategoriesWithSummary(universe);
   return finalize(universe);
 }
 
diff --git a/server/app/scanpy_engine/scanpy_engine.py b/server/app/scanpy_engine/scanpy_engine.py
index 8b1845a2f..b73341998 100644
--- a/server/app/scanpy_engine/scanpy_engine.py
+++ b/server/app/scanpy_engine/scanpy_engine.py
@@ -65,6 +65,22 @@ def _alias_annotation_names(self, axis, name):
         else:
             raise KeyError(f"Annotation name {name}, specified in --{ax_name}_name does not exist.")
 
+    @staticmethod
+    def _can_cast_to_float32(ann):
+        if ann.dtype.kind == "f" and np.can_cast(ann.dtype, np.float32):
+            return True
+        return False
+
+    @staticmethod
+    def _can_cast_to_int32(ann):
+        if ann.dtype.kind in ["i", "u"]:
+            if np.can_cast(ann.dtype, np.int32):
+                return True
+            ii32 = np.iinfo(np.int32)
+            if ann.min() >= ii32.min and ann.max() <= ii32.max:
+                return True
+        return False
+
     def _create_schema(self):
         self.schema = {
             "dataframe": {
@@ -81,16 +97,18 @@ def _create_schema(self):
             curr_axis = getattr(self.data, str(ax))
             for ann in curr_axis:
                 ann_schema = {"name": ann}
-                data_kind = curr_axis[ann].dtype.kind
-                if data_kind == "f":
+                dtype = curr_axis[ann].dtype
+                data_kind = dtype.kind
+
+                if self._can_cast_to_float32(curr_axis[ann]):
                     ann_schema["type"] = "float32"
-                elif data_kind in ["i", "u"]:
+                elif self._can_cast_to_int32(curr_axis[ann]):
                     ann_schema["type"] = "int32"
-                elif data_kind == "?":
+                elif dtype == np.bool_:
                     ann_schema["type"] = "boolean"
-                elif data_kind == "O" and curr_axis[ann].dtype == "object":
+                elif data_kind == "O" and dtype == "object":
                     ann_schema["type"] = "string"
-                elif data_kind == "O" and curr_axis[ann].dtype == "category":
+                elif data_kind == "O" and dtype == "category":
                     ann_schema["type"] = "categorical"
                     ann_schema["categories"] = curr_axis[ann].dtype.categories.tolist()
                 else: