diff --git a/packages/@aws-cdk/core/lib/context.ts b/packages/@aws-cdk/core/lib/context.ts
index 783623d4e4b3c..8d1efe83cd6ee 100644
--- a/packages/@aws-cdk/core/lib/context.ts
+++ b/packages/@aws-cdk/core/lib/context.ts
@@ -24,7 +24,12 @@ export class ContextProvider {
     /**
      * Read a provider value, verifying it's a string
      */
-    public getStringValue(provider: string, scope: string[], args: string[]): string {
+    public getStringValue(provider: string, scope: undefined | string[], args: string[], defaultValue = ''): string {
+        // if scope is undefined, this is probably a test mode, so we just
+        // return the default value
+        if (!scope) {
+            return defaultValue;
+        }
         const key = colonQuote([provider].concat(scope).concat(args)).join(':');
         const value = this.context.getContext(key);
         if (value != null) {
@@ -35,13 +40,19 @@ export class ContextProvider {
         }
 
         this.stack.reportMissingContext(key, { provider, scope, args });
-        return '';
+        return defaultValue;
     }
 
     /**
      * Read a provider value, verifying it's a list
      */
-    public getStringListValue(provider: string, scope: string[], args: string[], defaultValue = ['']): string[] {
+    public getStringListValue(provider: string, scope: undefined | string[], args: string[], defaultValue = ['']): string[] {
+        // if scope is undefined, this is probably a test mode, so we just
+        // return the default value
+        if (!scope) {
+            return defaultValue;
+        }
+
         const key = colonQuote([provider].concat(scope).concat(args)).join(':');
         const value = this.context.getContext(key);
 
@@ -59,7 +70,7 @@ export class ContextProvider {
     /**
      * Helper function to wrap up account and region into a scope tuple
      */
-    public accountRegionScope(providerDescription: string): string[] {
+    public accountRegionScope(providerDescription: string): undefined | string[] {
         const stack = Stack.find(this.context);
         if (!stack) {
             throw new Error(`${providerDescription}: construct must be in a stack`);
@@ -69,8 +80,7 @@ export class ContextProvider {
         const region = stack.env.region;
 
         if (account == null || region == null) {
-            // tslint:disable-next-line:max-line-length
-            throw new Error(`${providerDescription}: requires account and region information, but ${stack.name} doesn't have an "env" defined`);
+            return undefined;
         }
 
         return [account, region];
diff --git a/packages/@aws-cdk/core/test/test.context.ts b/packages/@aws-cdk/core/test/test.context.ts
index af525033a3716..7e94cf809c636 100644
--- a/packages/@aws-cdk/core/test/test.context.ts
+++ b/packages/@aws-cdk/core/test/test.context.ts
@@ -50,7 +50,14 @@ export = {
         test.deepEqual(azs, 'abc');
 
         test.done();
-    }
+    },
+
+    'Return default values if "env" is undefined to facilitate unit tests'(test: Test) {
+        const stack = new Stack();
+        test.deepEqual(new AvailabilityZoneProvider(stack).availabilityZones, [ 'dummy1a', 'dummy1b', 'dummy1c' ]);
+        test.deepEqual(new SSMParameterProvider(stack).getString('foo'), '');
+        test.done();
+    },
 };
 
 function firstKey(obj: any): string {