diff --git a/CHANGELOG.md b/CHANGELOG.md
index e568a20a1..13601b416 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ Dates are in `YYYY-MM-DD` format and versions are in [semantic versioning](http:
 -   [#514](https://github.com/wordplaydev/wordplay/issues/514) Fixed cursor position on hidden language tags.
 -   Fixed parsing bug that prevented complete parsing of the program.
 -   Fixed reactivity dependency bug that included evaluates in branch dependencies.
+-   Fixed selection of locale in evaluation.
 
 ## 0.10.4 2024-07-08
 
diff --git a/src/components/app/PlayView.svelte b/src/components/app/PlayView.svelte
index e17312a48..ba1ef827e 100644
--- a/src/components/app/PlayView.svelte
+++ b/src/components/app/PlayView.svelte
@@ -16,7 +16,7 @@
     let evaluator: Evaluator;
     let latest: Value | undefined = undefined;
     $: {
-        evaluator = new Evaluator(project, DB, $locales);
+        evaluator = new Evaluator(project, DB, $locales.getLocales());
         if (evaluator) {
             evaluator.stop();
             evaluator.ignore(update);
diff --git a/src/components/app/ProjectPreview.svelte b/src/components/app/ProjectPreview.svelte
index 9fd0420bd..e565c1ef5 100644
--- a/src/components/app/ProjectPreview.svelte
+++ b/src/components/app/ProjectPreview.svelte
@@ -34,7 +34,12 @@
     $: path = link ?? project.getLink(true);
 
     function updatePreview() {
-        const evaluator = new Evaluator(project, DB, $locales, false);
+        const evaluator = new Evaluator(
+            project,
+            DB,
+            $locales.getLocales(),
+            false,
+        );
         const value = evaluator.getInitialValue();
         evaluator.stop();
         const stage = value ? toStage(evaluator, value) : undefined;
diff --git a/src/components/concepts/ExampleUI.svelte b/src/components/concepts/ExampleUI.svelte
index 7a9d78012..4b0276071 100644
--- a/src/components/concepts/ExampleUI.svelte
+++ b/src/components/concepts/ExampleUI.svelte
@@ -35,7 +35,7 @@
         if (evaluator) evaluator.ignore(update);
 
         if (evaluated) {
-            evaluator = new Evaluator(project, DB, $locales);
+            evaluator = new Evaluator(project, DB, $locales.getLocales());
             evaluator.observe(update);
             evaluator.start();
         } else {
diff --git a/src/components/project/ProjectView.svelte b/src/components/project/ProjectView.svelte
index df20f0e71..dec546bfd 100644
--- a/src/components/project/ProjectView.svelte
+++ b/src/components/project/ProjectView.svelte
@@ -125,8 +125,9 @@
     import { AnimationFactorIcons } from '@db/AnimationFactorSetting';
     import { COPY_SYMBOL } from '@parser/Symbols';
     import CopyButton from './CopyButton.svelte';
-    import { toLocaleString } from '@locale/Locale';
+    import { toLocaleString, type Locale } from '@locale/Locale';
     import { default as ModeChooser } from '@components/widgets/Mode.svelte';
+    import DefaultLocale from '@locale/DefaultLocale';
 
     export let project: Project;
     export let original: Project | undefined = undefined;
@@ -227,6 +228,9 @@
     });
     setContext(KeyModfifierSymbol, keyModifiers);
 
+    /** Keep a currently selected output locale to send to the Evaluator for evaluation and rendering */
+    let evaluationLocale: Locale | undefined;
+
     // When keyboard edit idle changes to true, set a timeout
     // to reset it to false after a delay.
     $: {
@@ -324,7 +328,10 @@
         const newEvaluator = new Evaluator(
             newProject,
             DB,
-            newProject.getLocales(),
+            // Choose the selected evaluation locale or if not selected, currently selected IDE locale
+            evaluationLocale
+                ? [evaluationLocale, DefaultLocale]
+                : $locales.getLocales(),
             true,
             replayInputs ? $evaluator : undefined,
         );
diff --git a/src/edit/OutputExpression.ts b/src/edit/OutputExpression.ts
index 06a0102b0..9bde036a8 100644
--- a/src/edit/OutputExpression.ts
+++ b/src/edit/OutputExpression.ts
@@ -136,7 +136,7 @@ export default class OutputExpression {
                 expression instanceof Expression ? expression : undefined,
             value:
                 expression instanceof Literal
-                    ? expression.getValue(this.locales)
+                    ? expression.getValue(this.locales.getLocales())
                     : undefined,
         };
     }
diff --git a/src/edit/OutputProperties.ts b/src/edit/OutputProperties.ts
index 712baee20..970406ac0 100644
--- a/src/edit/OutputProperties.ts
+++ b/src/edit/OutputProperties.ts
@@ -27,7 +27,7 @@ function getPoseProperty(project: Project, name: NameAndDoc): OutputProperty {
             expr instanceof Evaluate &&
             (expr.is(project.shares.output.Pose, context) ||
                 expr.is(project.shares.output.Sequence, context)),
-        (locales) => createPoseLiteral(project, locales)
+        (locales) => createPoseLiteral(project, locales),
     );
 }
 
@@ -38,7 +38,7 @@ export function getDurationProperty(locales: Locales): OutputProperty {
         false,
         false,
         (expr) => expr instanceof NumberLiteral,
-        () => NumberLiteral.make(0.25, Unit.create(['s']))
+        () => NumberLiteral.make(0.25, Unit.create(['s'])),
     );
 }
 
@@ -51,26 +51,26 @@ export function getStyleProperty(locales: Locales): OutputProperty {
                     ...all,
                     ...(Array.isArray(next) ? next : [next]),
                 ],
-                []
+                [],
             ),
             true,
             (text: string) => TextLiteral.make(text),
             (expression: Expression | undefined) =>
                 expression instanceof TextLiteral
-                    ? expression.getValue(locales).text
-                    : undefined
+                    ? expression.getValue(locales.getLocales()).text
+                    : undefined,
         ),
         false,
         false,
         (expr) => expr instanceof TextLiteral,
-        () => TextLiteral.make(DefaultStyle)
+        () => TextLiteral.make(DefaultStyle),
     );
 }
 
 // All type output has these properties.
 export function getTypeOutputProperties(
     project: Project,
-    locales: Locales
+    locales: Locales,
 ): OutputProperty[] {
     return [
         new OutputProperty(
@@ -79,7 +79,7 @@ export function getTypeOutputProperties(
             false,
             true,
             (expr) => expr instanceof NumberLiteral,
-            () => NumberLiteral.make(1, Unit.meters())
+            () => NumberLiteral.make(1, Unit.meters()),
         ),
         new OutputProperty(
             locales.get((l) => l.output.Phrase.face),
@@ -89,13 +89,13 @@ export function getTypeOutputProperties(
                 (text: string) => TextLiteral.make(text),
                 (expression: Expression | undefined) =>
                     expression instanceof TextLiteral
-                        ? expression.getValue(locales).text
-                        : undefined
+                        ? expression.getValue(locales.getLocales()).text
+                        : undefined,
             ),
             false,
             true,
             (expr) => expr instanceof TextLiteral,
-            () => TextLiteral.make(locales.get((l) => l.ui.font.app))
+            () => TextLiteral.make(locales.get((l) => l.ui.font.app)),
         ),
         new OutputProperty(
             locales.get((l) => l.output.Phrase.place),
@@ -111,14 +111,14 @@ export function getTypeOutputProperties(
                 Evaluate.make(
                     Reference.make(
                         locales.getName(project.shares.output.Place.names),
-                        project.shares.output.Place
+                        project.shares.output.Place,
                     ),
                     [
                         NumberLiteral.make(0, Unit.meters()),
                         NumberLiteral.make(0, Unit.meters()),
                         NumberLiteral.make(0, Unit.meters()),
-                    ]
-                )
+                    ],
+                ),
         ),
         ...getOutputProperties(project, locales),
     ];
@@ -128,7 +128,7 @@ export function getTypeOutputProperties(
 // All type output has these properties, in this order.
 export function getOutputProperties(
     project: Project,
-    locales: Locales
+    locales: Locales,
 ): OutputProperty[] {
     return [
         new OutputProperty(
@@ -137,7 +137,7 @@ export function getOutputProperties(
             false,
             false,
             (expr) => expr instanceof TextLiteral,
-            () => TextLiteral.make('')
+            () => TextLiteral.make(''),
         ),
         new OutputProperty(
             locales.get((l) => l.output.Phrase.selectable),
@@ -145,24 +145,24 @@ export function getOutputProperties(
             false,
             false,
             (expr) => expr instanceof BooleanLiteral,
-            () => BooleanLiteral.make(false)
+            () => BooleanLiteral.make(false),
         ),
         ...getPoseProperties(project, locales, true),
         getPoseProperty(
             project,
-            locales.get((l) => l.output.Phrase.entering)
+            locales.get((l) => l.output.Phrase.entering),
         ),
         getPoseProperty(
             project,
-            locales.get((l) => l.output.Phrase.resting)
+            locales.get((l) => l.output.Phrase.resting),
         ),
         getPoseProperty(
             project,
-            locales.get((l) => l.output.Phrase.moving)
+            locales.get((l) => l.output.Phrase.moving),
         ),
         getPoseProperty(
             project,
-            locales.get((l) => l.output.Phrase.exiting)
+            locales.get((l) => l.output.Phrase.exiting),
         ),
         getDurationProperty(locales),
         getStyleProperty(locales),
diff --git a/src/examples/examples.test.ts b/src/examples/examples.test.ts
index b16ab722a..e4a039d0e 100644
--- a/src/examples/examples.test.ts
+++ b/src/examples/examples.test.ts
@@ -170,7 +170,12 @@ test.each([...projects])(
     `Ensure $name doesn't evaluate to exception`,
     async (example: SerializedProject) => {
         const project = await Project.deserialize(Locales, example);
-        const evaluator = new Evaluator(project, DB, DefaultLocales, false);
+        const evaluator = new Evaluator(
+            project,
+            DB,
+            DefaultLocales.getLocales(),
+            false,
+        );
         const value = evaluator.getInitialValue();
         evaluator.stop();
         expect(value).not.toBeInstanceOf(ExceptionValue);
diff --git a/src/nodes/FormattedLiteral.ts b/src/nodes/FormattedLiteral.ts
index 729991fe8..cbaec3f98 100644
--- a/src/nodes/FormattedLiteral.ts
+++ b/src/nodes/FormattedLiteral.ts
@@ -146,8 +146,8 @@ export default class FormattedLiteral extends Literal {
         return Glyphs.Formatted;
     }
 
-    getValue(locales: Locales): Value {
-        const preferred = this.getPreferredText(locales.getLocales());
+    getValue(locales: Locale[]): Value {
+        const preferred = this.getPreferredText(locales);
         return new MarkupValue(this, preferred.markup);
     }
 
diff --git a/src/nodes/Literal.ts b/src/nodes/Literal.ts
index 7e907320e..901a66d82 100644
--- a/src/nodes/Literal.ts
+++ b/src/nodes/Literal.ts
@@ -6,7 +6,7 @@ import SimpleExpression from './SimpleExpression';
 import type Expression from './Expression';
 import Purpose from '../concepts/Purpose';
 import type Context from './Context';
-import type Locales from '../locale/Locales';
+import type Locale from '@locale/Locale';
 
 export default abstract class Literal extends SimpleExpression {
     constructor() {
@@ -29,8 +29,8 @@ export default abstract class Literal extends SimpleExpression {
     evaluate(evaluator: Evaluator, prior: Value | undefined): Value {
         if (prior) return prior;
 
-        return this.getValue(evaluator.locales);
+        return this.getValue(evaluator.getLocales());
     }
 
-    abstract getValue(locales: Locales): Value;
+    abstract getValue(locales: Locale[]): Value;
 }
diff --git a/src/nodes/Program.test.ts b/src/nodes/Program.test.ts
index 84adeb49b..3c77df440 100644
--- a/src/nodes/Program.test.ts
+++ b/src/nodes/Program.test.ts
@@ -6,7 +6,6 @@ import Project from '../models/Project';
 import type Value from '../values/Value';
 import { DB } from '../db/Database';
 import DefaultLocale from '../locale/DefaultLocale';
-import Locales from '../locale/Locales';
 
 test.each([
     // A single source with 1 should evaluate to 1
@@ -23,14 +22,12 @@ test.each([
             code
                 .slice(1)
                 .map((code, index) => new Source(`sup${index + 1}`, code)),
-            DefaultLocale
+            DefaultLocale,
         );
-        const value = new Evaluator(
-            project,
-            DB,
-            new Locales([DefaultLocale], DefaultLocale)
-        ).getInitialValue();
+        const value = new Evaluator(project, DB, [
+            DefaultLocale,
+        ]).getInitialValue();
         expect(value).toBeDefined();
         expect((value as Value).constructor).toBe(valueType);
-    }
+    },
 );
diff --git a/src/nodes/Reaction.test.ts b/src/nodes/Reaction.test.ts
index 264ab141a..a0cb97a6d 100644
--- a/src/nodes/Reaction.test.ts
+++ b/src/nodes/Reaction.test.ts
@@ -11,7 +11,6 @@ import Reaction from './Reaction';
 import ExpectedStream from '../conflicts/ExpectedStream';
 import { DB } from '../db/Database';
 import DefaultLocale from '../locale/DefaultLocale';
-import Locales from '../locale/Locales';
 
 const makeOne = (creator: Expression) => Time.make(creator, 1);
 
@@ -46,16 +45,12 @@ test.each([
         code: string,
         value: (expression: Expression) => Value,
         expectedInitial: string,
-        expectedNext: string
+        expectedNext: string,
     ) => {
         // Make the project
         const source = new Source('test', code);
         const project = Project.make(null, 'test', source, [], DefaultLocale);
-        const evaluator = new Evaluator(
-            project,
-            DB,
-            new Locales([DefaultLocale], DefaultLocale)
-        );
+        const evaluator = new Evaluator(project, DB, [DefaultLocale]);
 
         evaluator.start();
 
@@ -75,7 +70,7 @@ test.each([
         const actualNext = evaluator.getLatestSourceValue(source);
         expect(actualNext?.toString()).toBe(expectedNext);
         evaluator.stop();
-    }
+    },
 );
 
 testConflict('1 … ∆ Time() … 1 + .', '1 … ⊤ … 1 + .', Reaction, ExpectedStream);
diff --git a/src/nodes/TextLiteral.ts b/src/nodes/TextLiteral.ts
index c59d6da2e..9347638fd 100644
--- a/src/nodes/TextLiteral.ts
+++ b/src/nodes/TextLiteral.ts
@@ -178,9 +178,9 @@ export default class TextLiteral extends Literal {
             : getPreferred(locales, this.texts);
     }
 
-    getValue(locales: Locales): TextValue {
+    getValue(locales: Locale[]): TextValue {
         // Get the alternatives
-        const best = this.getLocaleText(locales.getLocales());
+        const best = this.getLocaleText(locales);
         return new TextValue(
             this,
             best.getText(),
diff --git a/src/runtime/Evaluator.test.ts b/src/runtime/Evaluator.test.ts
index 2d8de1b81..444902f9b 100644
--- a/src/runtime/Evaluator.test.ts
+++ b/src/runtime/Evaluator.test.ts
@@ -15,7 +15,7 @@ test.each([0, 1, 10, 15])('Step back %i', (steps: number) => {
 
     const source = new Source('test', fib);
     const project = Project.make(null, 'test', source, [], DefaultLocale);
-    const evaluator = new Evaluator(project, DB, DefaultLocales);
+    const evaluator = new Evaluator(project, DB, DefaultLocales.getLocales());
     evaluator.start();
     const stepIndex = evaluator.getStepIndex();
 
@@ -38,7 +38,7 @@ test('Too many steps', () => {
 
     const source = new Source('test', fib);
     const project = Project.make(null, 'test', source, [], DefaultLocale);
-    const evaluator = new Evaluator(project, DB, DefaultLocales);
+    const evaluator = new Evaluator(project, DB, DefaultLocales.getLocales());
     const value = evaluator.getInitialValue();
     expect(value).toBeInstanceOf(StepLimitException);
 });
@@ -51,7 +51,7 @@ test('Too many evaluations', () => {
 
     const source = new Source('test', fib);
     const project = Project.make(null, 'test', source, [], DefaultLocale);
-    const evaluator = new Evaluator(project, DB, DefaultLocales);
+    const evaluator = new Evaluator(project, DB, DefaultLocales.getLocales());
     const value = evaluator.getInitialValue();
     expect(value).toBeInstanceOf(EvaluationLimitException);
 });
diff --git a/src/runtime/Evaluator.ts b/src/runtime/Evaluator.ts
index d3985f5bd..b6382e1c5 100644
--- a/src/runtime/Evaluator.ts
+++ b/src/runtime/Evaluator.ts
@@ -37,7 +37,6 @@ import NumberGenerator from 'recoverable-random';
 import type { Database } from '../db/Database';
 import ReactionStream from '../values/ReactionStream';
 import type Animator from '../output/Animator';
-import Locales from '../locale/Locales';
 import DefaultLocale from '../locale/DefaultLocale';
 import StructureValue from '@values/StructureValue';
 import ListValue from '@values/ListValue';
@@ -83,7 +82,7 @@ export default class Evaluator {
     readonly project: Project;
 
     /** The preferred locales for evaluation. */
-    readonly locales: Locales;
+    readonly locales: Locale[];
 
     /** The database that contains settings for evaluation */
     readonly database: Database;
@@ -259,7 +258,7 @@ export default class Evaluator {
     constructor(
         project: Project,
         database: Database,
-        locales: Locales,
+        locales: Locale[],
         reactive = true,
         prior: Evaluator | undefined = undefined,
     ) {
@@ -313,11 +312,10 @@ export default class Evaluator {
             ),
             locale,
         );
-        return new Evaluator(
-            project,
-            database,
-            new Locales([locale], DefaultLocale),
-        ).getInitialValue();
+        return new Evaluator(project, database, [
+            locale,
+            DefaultLocale,
+        ]).getInitialValue();
     }
 
     /** Mirror the given evaluator's stream history and state, but with the new source. */
@@ -434,7 +432,7 @@ export default class Evaluator {
 
     /** Get the currently selected locales from the database */
     getLocales() {
-        return this.locales.getLocales();
+        return this.locales;
     }
 
     getCurrentEvaluation() {
diff --git a/src/runtime/evaluate.ts b/src/runtime/evaluate.ts
index 847f407c6..e355fdfe6 100644
--- a/src/runtime/evaluate.ts
+++ b/src/runtime/evaluate.ts
@@ -13,7 +13,7 @@ import Evaluator from './Evaluator';
 export default function evaluateCode(
     main: string,
     supplements?: string[],
-    locales?: Locales
+    locales?: Locales,
 ): Value | undefined {
     const source = new Source('test', main);
     const project = Project.make(
@@ -21,16 +21,13 @@ export default function evaluateCode(
         'test',
         source,
         (supplements ?? []).map(
-            (code, index) => new Source(`sup${index + 1}`, code)
+            (code, index) => new Source(`sup${index + 1}`, code),
         ),
-        locales?.getLocales() ?? DefaultLocale
+        locales?.getLocales() ?? DefaultLocale,
     );
     return new Evaluator(
         project,
         DB,
-        new Locales(
-            locales === undefined ? [DefaultLocale] : locales.getLocales(),
-            DefaultLocale
-        )
+        locales === undefined ? [DefaultLocale] : locales.getLocales(),
     ).getInitialValue();
 }