diff --git a/gui/src/app/SPAnalysis/SPAnalysisContextProvider.tsx b/gui/src/app/SPAnalysis/SPAnalysisContextProvider.tsx
index ddad1ed7..d044ee7e 100644
--- a/gui/src/app/SPAnalysis/SPAnalysisContextProvider.tsx
+++ b/gui/src/app/SPAnalysis/SPAnalysisContextProvider.tsx
@@ -11,6 +11,7 @@ type SPAnalysisContextType = {
 }
 
 type SPAnalysisContextProviderProps = {
+    //
 }
 
 export const SPAnalysisContext = createContext<SPAnalysisContextType>({
diff --git a/gui/src/app/pages/HomePage/HomePage.tsx b/gui/src/app/pages/HomePage/HomePage.tsx
index 4ba0e1c2..cbb57fb5 100644
--- a/gui/src/app/pages/HomePage/HomePage.tsx
+++ b/gui/src/app/pages/HomePage/HomePage.tsx
@@ -1,5 +1,5 @@
 import { Splitter } from "@fi-sci/splitter";
-import { FunctionComponent, useCallback, useContext, useEffect, useMemo, useState } from "react";
+import { FunctionComponent, useCallback, useContext, useEffect, useMemo, useRef, useState } from "react";
 import DataFileEditor from "../../FileEditor/DataFileEditor";
 import StanFileEditor from "../../FileEditor/StanFileEditor";
 import RunPanel from "../../RunPanel/RunPanel";
@@ -30,8 +30,6 @@ const HomePage: FunctionComponent<Props> = ({ width, height }) => {
 }
 
 const HomePageChild: FunctionComponent<Props> = ({ width, height }) => {
-
-
     const { data, update } = useContext(SPAnalysisContext)
     const setSamplingOpts = useCallback((opts: SamplingOpts) => {
         update({ type: 'setSamplingOpts', opts })
@@ -39,14 +37,29 @@ const HomePageChild: FunctionComponent<Props> = ({ width, height }) => {
 
     const [compiledMainJsUrl, setCompiledMainJsUrl] = useState<string>('')
 
-    const leftPanelWidth = Math.max(250, Math.min(340, width * 0.2))
+    const [leftPanelCollapsed, setLeftPanelCollapsed] = useState(determineShouldBeInitiallyCollapsed(width))
+    const expandedLeftPanelWidth = determineLeftPanelWidth(width) // what the width would be if expanded
+    const leftPanelWidth = leftPanelCollapsed ? 20 : expandedLeftPanelWidth // the actual width
+
+    // We automatically collapse the panel if user has resized the window to be
+    // too small but we only want to do this right when we cross the threshold,
+    // not every time we resize by a pixel. Similar for expanding the panel when
+    // we cross the threshold in the other direction.
+    const lastShouldBeCollapsed = useRef(determineShouldBeInitiallyCollapsed(width))
+    useEffect(() => {
+        const shouldBeCollapsed = determineShouldBeInitiallyCollapsed(width)
+        if (shouldBeCollapsed !== lastShouldBeCollapsed.current) {
+            lastShouldBeCollapsed.current = shouldBeCollapsed
+            setLeftPanelCollapsed(shouldBeCollapsed)
+        }
+    }, [width])
+
     const topBarHeight = 25
 
     useEffect(() => {
         document.title = "Stan Playground - " + data.meta.title;
     }, [data.meta.title])
 
-
     return (
         <div style={{ position: 'absolute', width, height, overflow: 'hidden' }}>
             <div className="top-bar" style={{ position: 'absolute', left: 0, top: 0, width, height: topBarHeight, overflow: 'hidden' }}>
@@ -58,6 +71,8 @@ const HomePageChild: FunctionComponent<Props> = ({ width, height }) => {
             </div>
             <div className="left-panel" style={{ position: 'absolute', left: 0, top: topBarHeight + 2, width: leftPanelWidth, height: height - topBarHeight - 2, overflow: 'auto' }}>
                 <LeftPanel
+                    collapsed={leftPanelCollapsed}
+                    onSetCollapsed={setLeftPanelCollapsed}
                     width={leftPanelWidth}
                     height={height - topBarHeight - 2}
                     hasUnsavedChanges={modelHasUnsavedChanges(data)}
@@ -100,6 +115,19 @@ const HomePageChild: FunctionComponent<Props> = ({ width, height }) => {
     )
 }
 
+// the width of the left panel when it is expanded based on the overall width
+const determineLeftPanelWidth = (width: number) => {
+    const minWidth = 250
+    const maxWidth = 400
+    return Math.min(maxWidth, Math.max(minWidth, width / 4))
+}
+
+// whether the left panel should be collapsed initially based on the overall
+// width
+const determineShouldBeInitiallyCollapsed = (width: number) => {
+    return width < 800
+}
+
 type RightViewProps = {
     width: number
     height: number
diff --git a/gui/src/app/pages/HomePage/LeftPanel.tsx b/gui/src/app/pages/HomePage/LeftPanel.tsx
index 554758ce..30c7a362 100644
--- a/gui/src/app/pages/HomePage/LeftPanel.tsx
+++ b/gui/src/app/pages/HomePage/LeftPanel.tsx
@@ -1,18 +1,21 @@
-import { Hyperlink } from "@fi-sci/misc"
+import { Hyperlink, SmallIconButton } from "@fi-sci/misc"
 import ModalWindow, { useModalWindow } from "@fi-sci/modal-window"
 import { FunctionComponent, useCallback, useContext } from "react"
 import examplesStanies, { Stanie } from "../../exampleStanies/exampleStanies"
 import { SPAnalysisContext } from "../../SPAnalysis/SPAnalysisContextProvider"
 import ExportWindow from "./ExportWindow"
 import ImportWindow from "./ImportWindow"
+import { ChevronLeft, ChevronRight } from "@mui/icons-material"
 
 type LeftPanelProps = {
     width: number
     height: number
     hasUnsavedChanges: boolean
+    collapsed: boolean
+    onSetCollapsed: (collapsed: boolean) => void
 }
 
-const LeftPanel: FunctionComponent<LeftPanelProps> = ({ width, height, hasUnsavedChanges }) => {
+const LeftPanel: FunctionComponent<LeftPanelProps> = ({ width, height, hasUnsavedChanges, collapsed, onSetCollapsed }) => {
     // note: this is close enough to pass in directly if we wish
     const { update } = useContext(SPAnalysisContext)
 
@@ -22,9 +25,21 @@ const LeftPanel: FunctionComponent<LeftPanelProps> = ({ width, height, hasUnsave
 
     const { visible: exportVisible, handleOpen: exportOpen, handleClose: exportClose } = useModalWindow()
     const { visible: importVisible, handleOpen: importOpen, handleClose: importClose } = useModalWindow()
+
+    if (collapsed) {
+        return (
+            <div style={{position: 'absolute', width, height, backgroundColor: 'lightgray', overflowY: 'auto'}}>
+                <div style={{margin: 5}}>
+                    <ExpandButton onClick={() => onSetCollapsed(false)} />
+                </div>
+            </div>
+        )
+    }
+
     return (
         <div style={{position: 'absolute', width, height, backgroundColor: 'lightgray', overflowY: 'auto'}}>
             <div style={{margin: 5}}>
+                <CollapseButton onClick={() => onSetCollapsed(true)} />
                 <h3>Examples</h3>
                 {
                     examplesStanies.map((stanie, i) => (
@@ -85,4 +100,24 @@ const LeftPanel: FunctionComponent<LeftPanelProps> = ({ width, height, hasUnsave
     )
 }
 
+const ExpandButton: FunctionComponent<{ onClick: () => void }> = ({ onClick }) => {
+    return (
+        <SmallIconButton
+            icon={<ChevronRight />}
+            onClick={onClick}
+            title="Expand"
+        />
+    )
+}
+
+const CollapseButton: FunctionComponent<{ onClick: () => void }> = ({ onClick }) => {
+    return (
+        <SmallIconButton
+            icon={<ChevronLeft />}
+            onClick={onClick}
+            title="Collapse"
+        />
+    )
+}
+
 export default LeftPanel
\ No newline at end of file