diff --git a/src/client/types/number.type-renderer.jsx b/src/client/types/number.type-renderer.jsx
index c11594c..8a2d00a 100644
--- a/src/client/types/number.type-renderer.jsx
+++ b/src/client/types/number.type-renderer.jsx
@@ -10,6 +10,10 @@ const decorate = compose(
 );
 
 const Number = ({
+  dispatchers: {
+    onChange = () => {},
+    onIncrement = () => {},
+  },
   options,
   value,
 }) => (
@@ -26,14 +30,24 @@ const Number = ({
         : (
           <>
             <input
+              onChange={(event) => onChange(event.target.value)}
               // onWheel={(e) => (e.preventDefault(), false)}
-              readOnly
               type="text"
               value={value}
             />
             <div className="controls">
-              <button type="button">+</button>
-              <button type="button">-</button>
+              <button
+                onClick={() => onIncrement(1)}
+                type="button"
+              >
+                +
+              </button>
+              <button
+                onClick={() => onIncrement(-1)}
+                type="button"
+              >
+                -
+              </button>
             </div>
           </>
         )
diff --git a/src/common/resources/entity/state.js b/src/common/resources/entity/state.js
index 6fea5d4..0b8c976 100644
--- a/src/common/resources/entity/state.js
+++ b/src/common/resources/entity/state.js
@@ -67,6 +67,22 @@ const slice = createSlice({
   name: 'entities',
   initialState: adapter.getInitialState({uris: {}}),
   reducers: {
+    incrementTraitProperty: (state, {
+      payload: {
+        target,
+        trait,
+        type,
+        key,
+        value,
+      },
+    }) => {
+      const {traits} = state.entities[target];
+      traits[trait] = traits[trait] || {};
+      traits[trait][type] = traits[trait][type] || {};
+      traits[trait][type][key] = traits[trait][type][key] || 0;
+      traits[trait][type][key] += parseFloat(value);
+      state.entities[target].traits = traits;
+    },
     setTraitProperty: (state, {
       payload: {
         target,
@@ -94,6 +110,7 @@ const slice = createSlice({
 });
 
 export const {
+  incrementTraitProperty,
   setTraitProperty,
 } = slice.actions;
 
diff --git a/src/common/resources/entity/trait-pane.jsx b/src/common/resources/entity/trait-pane.jsx
index 3afed1f..3814fef 100644
--- a/src/common/resources/entity/trait-pane.jsx
+++ b/src/common/resources/entity/trait-pane.jsx
@@ -7,7 +7,7 @@ import {useDispatch} from 'react-redux';
 
 import Value from '~/client/value';
 
-import {setTraitProperty} from './state';
+import {incrementTraitProperty, setTraitProperty} from './state';
 
 let TraitComponents;
 const ensureTraitComponents = () => {
@@ -52,6 +52,13 @@ const makePane = (context, dispatch, target, type) => (trait) => {
                 key,
                 value,
               })),
+              onIncrement: (value) => dispatch(incrementTraitProperty({
+                target,
+                trait: type,
+                type: traitHalf,
+                key,
+                value,
+              })),
             }}
             options={options}
             value={values[key]}