diff --git a/src/RJSObject.mm b/src/RJSObject.mm
index c5f77bef..2405e1ca 100644
--- a/src/RJSObject.mm
+++ b/src/RJSObject.mm
@@ -33,12 +33,14 @@ JSValueRef ObjectGetProperty(JSContextRef ctx, JSObjectRef jsObject, JSStringRef
     try {
         Object *obj = RJSGetInternal<Object *>(jsObject);
         return obj->get_property_value<JSValueRef>(ctx, RJSStringForJSString(jsPropertyName));
+    } catch (InvalidPropertyException &ex) {
+        // getters for nonexistent properties in JS should always return undefined
     } catch (std::exception &ex) {
         if (exception) {
             *exception = RJSMakeError(ctx, ex);
         }
-        return NULL;
     }
+    return NULL;
 }
 
 bool ObjectSetProperty(JSContextRef ctx, JSObjectRef jsObject, JSStringRef jsPropertyName, JSValueRef value, JSValueRef* exception) {
diff --git a/src/object-store/object_accessor.hpp b/src/object-store/object_accessor.hpp
index 5636a2cb..25d79dfd 100644
--- a/src/object-store/object_accessor.hpp
+++ b/src/object-store/object_accessor.hpp
@@ -99,6 +99,28 @@ namespace realm {
         static Mixed to_mixed(ContextType ctx, ValueType &val) { throw std::runtime_error("'Any' type is unsupported"); }
     };
 
+    class InvalidPropertyException : public std::runtime_error
+    {
+      public:
+        InvalidPropertyException(const std::string object_type, const std::string property_name, const std::string message) : std::runtime_error(message), object_type(object_type), property_name(property_name) {}
+        const std::string object_type;
+        const std::string property_name;
+    };
+
+    class MissingPropertyValueException : public std::runtime_error
+    {
+    public:
+        MissingPropertyValueException(const std::string object_type, const std::string property_name, const std::string message) : std::runtime_error(message), object_type(object_type), property_name(property_name) {}
+        const std::string object_type;
+        const std::string property_name;
+    };
+
+    class MutationOutsideTransactionException : public std::runtime_error
+    {
+      public:
+        MutationOutsideTransactionException(std::string message) : std::runtime_error(message) {}
+    };
+
     //
     // template method implementations
     //
@@ -107,7 +129,8 @@ namespace realm {
     {
         const Property *prop = object_schema.property_for_name(prop_name);
         if (!prop) {
-            throw std::runtime_error("Setting invalid property '" + prop_name + "' on object '" + object_schema.name + "'.");
+            throw InvalidPropertyException(object_schema.name, prop_name,
+                "Setting invalid property '" + prop_name + "' on object '" + object_schema.name + "'.");
         }
         set_property_value_impl(ctx, *prop, value, try_update);
     };
@@ -117,7 +140,8 @@ namespace realm {
     {
         const Property *prop = object_schema.property_for_name(prop_name);
         if (!prop) {
-            throw std::runtime_error("Setting invalid property '" + prop_name + "' on object '" + object_schema.name + "'.");
+            throw InvalidPropertyException(object_schema.name, prop_name,
+                "Getting invalid property '" + prop_name + "' on object '" + object_schema.name + "'.");
         }
         return get_property_value_impl<ValueType>(ctx, *prop);
     };
@@ -128,7 +152,7 @@ namespace realm {
         using Accessor = NativeAccessor<ValueType, ContextType>;
 
         if (!m_realm->is_in_transaction()) {
-            throw std::runtime_error("Can only set property values within a transaction.");
+            throw MutationOutsideTransactionException("Can only set property values within a transaction.");
         }
 
         size_t column = property.table_column;
@@ -223,7 +247,7 @@ namespace realm {
         using Accessor = NativeAccessor<ValueType, ContextType>;
 
         if (!realm->is_in_transaction()) {
-            throw std::runtime_error("Can only create objects within a transaction.");
+            throw MutationOutsideTransactionException("Can only create objects within a transaction.");
         }
 
         // get or create our accessor
@@ -244,7 +268,8 @@ namespace realm {
             }
 
             if (!try_update && row_index != realm::not_found) {
-                throw std::runtime_error("Attempting to create an object of type '" + object_schema.name + "' with an exising primary key value.");
+                throw DuplicatePrimaryKeyValueException(object_schema.name, *primary_prop,
+                    "Attempting to create an object of type '" + object_schema.name + "' with an exising primary key value.");
             }
         }
 
@@ -267,7 +292,8 @@ namespace realm {
                         object.set_property_value_impl(ctx, prop, Accessor::default_value_for_property(ctx, realm.get(), object_schema, prop.name), try_update);
                     }
                     else {
-                        throw std::runtime_error("Missing property value for property " + prop.name);
+                        throw MissingPropertyValueException(object_schema.name, prop.name,
+                            "Missing property value for property " + prop.name);
                     }
                 }
             }
diff --git a/src/object-store/object_store.cpp b/src/object-store/object_store.cpp
index 59b94f3b..c282e20b 100644
--- a/src/object-store/object_store.cpp
+++ b/src/object-store/object_store.cpp
@@ -514,8 +514,12 @@ DuplicatePrimaryKeyValueException::DuplicatePrimaryKeyValueException(std::string
     m_object_type(object_type), m_property(property)
 {
     m_what = "Primary key property '" + property.name + "' has duplicate values after migration.";
-};
+}
 
+DuplicatePrimaryKeyValueException::DuplicatePrimaryKeyValueException(std::string const& object_type, Property const& property, const std::string message) : m_object_type(object_type), m_property(property)
+{
+    m_what = message;
+}
 
 SchemaValidationException::SchemaValidationException(std::vector<ObjectSchemaValidationException> const& errors) :
     m_validation_errors(errors)
@@ -600,3 +604,4 @@ DuplicatePrimaryKeysException::DuplicatePrimaryKeysException(std::string const&
 {
     m_what = "Duplicate primary keys for object '" + object_type + "'.";
 }
+
diff --git a/src/object-store/object_store.hpp b/src/object-store/object_store.hpp
index f38524f8..9972b089 100644
--- a/src/object-store/object_store.hpp
+++ b/src/object-store/object_store.hpp
@@ -137,6 +137,8 @@ namespace realm {
     class DuplicatePrimaryKeyValueException : public MigrationException {
       public:
         DuplicatePrimaryKeyValueException(std::string const& object_type, Property const& property);
+        DuplicatePrimaryKeyValueException(std::string const& object_type, Property const& property, const std::string message);
+
         std::string object_type() const { return m_object_type; }
         Property const& property() const { return m_property; }
       private:
diff --git a/tests/ObjectTests.js b/tests/ObjectTests.js
index 51f35e92..47aab7ab 100644
--- a/tests/ObjectTests.js
+++ b/tests/ObjectTests.js
@@ -44,6 +44,8 @@ module.exports = BaseTest.extend({
                 TestCase.assertEqual(object[prop.name], basicTypesValues[i]);
             }
         }
+
+        TestCase.assertEqual(object.nonexistent, undefined);
     },
     testBasicTypesPropertySetters: function() {
         var basicTypesValues = [true, 1, 1.1, 1.11, 'string', new Date(1), 'DATA'];