diff --git a/node-preload-legacy-require.js b/node-preload-legacy-require.js
index 94b158d..a1e5de6 100644
--- a/node-preload-legacy-require.js
+++ b/node-preload-legacy-require.js
@@ -11,17 +11,17 @@ function generateRequire(filename) {
 	return `--require ${filename}`;
 }
 
-function processNodePath(value) {
+function processNodePath(value, dir) {
 	const existing = value === '' ? [] : value.split(path.delimiter);
-	if (existing.includes(__dirname)) {
+	if (existing.includes(dir)) {
 		return value;
 	}
 
-	return existing.concat(__dirname).join(path.delimiter);
+	return existing.concat(dir).join(path.delimiter);
 }
 
 module.exports = {
 	generateRequire,
 	processNodePath,
-	needsPathEnv: __dirname.includes(' ')
+	needsPathEnv: dir => dir.includes(' ')
 };
diff --git a/node-preload-modern-require.js b/node-preload-modern-require.js
index 72835ab..37e176c 100644
--- a/node-preload-modern-require.js
+++ b/node-preload-modern-require.js
@@ -8,5 +8,5 @@ module.exports = {
 	generateRequire,
 	// The export explicitly exists but is undefined as it will never be called
 	processNodePath: undefined,
-	needsPathEnv: false
+	needsPathEnv: () => false
 };
diff --git a/node-preload-singleton.js b/node-preload-singleton.js
index d3b61bb..b52014b 100644
--- a/node-preload-singleton.js
+++ b/node-preload-singleton.js
@@ -65,20 +65,36 @@ function findPreloadModule() {
 }
 
 const nodeOptionRequireSelf = generateRequire(require.resolve('./node-preload.js'));
+/* istanbul ignore next: yarn specific */
+const pnpapiFile = () => process.versions.pnp && require.resolve('pnpapi');
+
 const preloadList = loadPreloadList();
 const propagate = loadPropagated();
 const preloadModule = findPreloadModule();
 
 function processNodeOptions(value) {
-	if (value.includes(nodeOptionRequireSelf)) {
-		return value;
+	/* istanbul ignore next: yarn specific */
+	const requirePNPAPI = (process.versions.pnp && generateRequire(pnpapiFile())) || '';
+	/* istanbul ignore next: yarn specific */
+	if (process.versions.pnp) {
+		/* Need pnpapi to be first, remove so we can reinsert before node-preload */
+		value = value.replace(requirePNPAPI, '');
+	}
+
+	if (!value.includes(nodeOptionRequireSelf)) {
+		if (value !== '') {
+			value = ' ' + value;
+		}
+
+		value = `${nodeOptionRequireSelf}${value}`;
 	}
 
-	if (value !== '') {
-		value = ' ' + value;
+	/* istanbul ignore next: yarn specific */
+	if (process.versions.pnp) {
+		value = `${requirePNPAPI} ${value}`;
 	}
 
-	return `${nodeOptionRequireSelf}${value}`;
+	return value;
 }
 
 function processEnvPairs(options) {
@@ -94,8 +110,16 @@ function processEnvPairs(options) {
 	env.NODE_POLYFILL_PRELOAD = preloadList.join(path.delimiter);
 
 	/* istanbul ignore next */
-	if (needsPathEnv) {
-		env.NODE_PATH = processNodePath(env.NODE_PATH || '');
+	if (needsPathEnv(__dirname)) {
+		env.NODE_PATH = processNodePath(env.NODE_PATH || '', __dirname);
+	}
+
+	/* istanbul ignore next: yarn specific */
+	if (process.versions.pnp) {
+		const pnpapiDir = path.dirname(pnpapiFile());
+		if (needsPathEnv(pnpapiDir)) {
+			env.NODE_PATH = processNodePath(env.NODE_PATH || '', pnpapiDir);
+		}
 	}
 
 	env.NODE_POLYFILL_PROPAGATE_ENV = JSON.stringify(Object.keys(propagate));
diff --git a/test/legacy-require.js b/test/legacy-require.js
index 35dcbef..f8b8b6c 100644
--- a/test/legacy-require.js
+++ b/test/legacy-require.js
@@ -9,11 +9,12 @@ const noSpaceFile = path.resolve('/dir/file.js');
 const spaceFile = path.resolve('/space dir/file.js');
 
 test('exports', async t => {
-	t.is(typeof legacyRequire, 'object');
+	t.type(legacyRequire, 'object');
 	t.deepEqual(Object.keys(legacyRequire).sort(), ['generateRequire', 'needsPathEnv', 'processNodePath']);
-	t.is(typeof generateRequire, 'function');
-	t.is(typeof processNodePath, 'function');
-	t.is(needsPathEnv, __dirname.includes(' '));
+	t.type(generateRequire, 'function');
+	t.type(processNodePath, 'function');
+	t.is(needsPathEnv(noSpaceFile), false);
+	t.is(needsPathEnv(spaceFile), true);
 });
 
 test('generateRequire', async t => {
@@ -29,8 +30,8 @@ test('generateRequire', async t => {
 test('processNodePath', async t => {
 	const dirname = path.resolve(__dirname, '..');
 
-	t.is(processNodePath(''), dirname);
-	t.is(processNodePath(dirname), dirname);
-	t.is(processNodePath([dirname, __dirname].join(path.delimiter)), [dirname, __dirname].join(path.delimiter));
-	t.is(processNodePath(__dirname), [__dirname, dirname].join(path.delimiter));
+	t.is(processNodePath('', dirname), dirname);
+	t.is(processNodePath(dirname, dirname), dirname);
+	t.is(processNodePath([dirname, __dirname].join(path.delimiter), dirname), [dirname, __dirname].join(path.delimiter));
+	t.is(processNodePath(__dirname, dirname), [__dirname, dirname].join(path.delimiter));
 });
diff --git a/test/modern-require.js b/test/modern-require.js
index 8ae4ee2..1c8f208 100644
--- a/test/modern-require.js
+++ b/test/modern-require.js
@@ -9,11 +9,13 @@ const noSpaceFile = path.resolve('/dir/file.js');
 const spaceFile = path.resolve('/space dir/file.js');
 
 test('exports', async t => {
-	t.is(typeof modernRequire, 'object');
+	t.type(modernRequire, 'object');
 	t.deepEqual(Object.keys(modernRequire).sort(), ['generateRequire', 'needsPathEnv', 'processNodePath']);
-	t.is(typeof generateRequire, 'function');
+	t.type(generateRequire, 'function');
 	t.is(processNodePath, undefined);
-	t.is(needsPathEnv, false);
+	t.type(needsPathEnv, 'function');
+	t.is(needsPathEnv(noSpaceFile), false);
+	t.is(needsPathEnv(spaceFile), false);
 });
 
 test('generateRequire', async t => {