diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenConstants.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenConstants.java
index f5c759d4d04..aacb5f2737e 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenConstants.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenConstants.java
@@ -144,4 +144,7 @@ public class CodegenConstants {
 
     public static final String GENERATE_PROPERTY_CHANGED = "generatePropertyChanged";
     public static final String GENERATE_PROPERTY_CHANGED_DESC = "Specifies that models support raising property changed events.";
+
+    public static final String NON_PUBLIC_API = "nonPublicApi";
+    public static final String NON_PUBLIC_API_DESC = "Generates code with reduced access modifiers; allows embedding elsewhere without exposing non-public API calls to consumers.";
 }
diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/CSharpClientCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/CSharpClientCodegen.java
index cf4bc656d83..526fffeda18 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/CSharpClientCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/CSharpClientCodegen.java
@@ -45,6 +45,9 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
     protected Map<Character, String> regexModifiers;
     protected final Map<String, String> frameworks;
 
+    // By default, generated code is considered public
+    protected boolean nonPublicApi = Boolean.FALSE;
+
     public CSharpClientCodegen() {
         super();
         modelTemplateFiles.put("model.mustache", ".cs");
@@ -130,6 +133,14 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
                 CodegenConstants.PACKAGE_DESCRIPTION_DESC,
                 this.generatePropertyChanged);
 
+        // NOTE: This will reduce visibility of all public members in templates. Users can use InternalsVisibleTo
+        // https://msdn.microsoft.com/en-us/library/system.runtime.compilerservices.internalsvisibletoattribute(v=vs.110).aspx
+        // to expose to shared code if the generated code is not embedded into another project. Otherwise, users of codegen
+        // should rely on default public visibility.
+        addSwitch(CodegenConstants.NON_PUBLIC_API,
+                CodegenConstants.NON_PUBLIC_API_DESC,
+                this.nonPublicApi);
+
         regexModifiers = new HashMap<Character, String>();
         regexModifiers.put('i', "IgnoreCase");
         regexModifiers.put('m', "Multiline");
@@ -232,6 +243,10 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
                     .get(CodegenConstants.OPTIONAL_ASSEMBLY_INFO).toString()));
         }
 
+        if (additionalProperties.containsKey(CodegenConstants.NON_PUBLIC_API)) {
+            setNonPublicApi(Boolean.valueOf(additionalProperties.get(CodegenConstants.NON_PUBLIC_API).toString()));
+        }
+
         final String testPackageName = testPackageName();
         String packageFolder = sourceFolder + File.separator + packageName;
         String clientPackageDir = packageFolder + File.separator + clientPackage;
@@ -555,6 +570,14 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
         this.generatePropertyChanged = generatePropertyChanged;
     }
 
+    public boolean isNonPublicApi() {
+        return nonPublicApi;
+    }
+
+    public void setNonPublicApi(final boolean nonPublicApi) {
+        this.nonPublicApi = nonPublicApi;
+    }
+
     @Override
     public String toModelDocFilename(String name) {
         return toModelFilename(name);
diff --git a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
index 33b631280c2..8960ccfe59e 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
@@ -19,7 +19,7 @@ namespace {{packageName}}.Client
     /// <summary>
     /// API client is mainly responsible for making the HTTP call to the API backend.
     /// </summary>
-    public partial class ApiClient
+    {{>visibility}} partial class ApiClient
     {
         private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
         {
diff --git a/modules/swagger-codegen/src/main/resources/csharp/ApiException.mustache b/modules/swagger-codegen/src/main/resources/csharp/ApiException.mustache
index ad7c2264d78..ca8044580f2 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ApiException.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ApiException.mustache
@@ -6,7 +6,7 @@ namespace {{packageName}}.Client
     /// <summary>
     /// API Exception
     /// </summary>
-    public class ApiException : Exception
+    {{>visibility}} class ApiException : Exception
     {
         /// <summary>
         /// Gets or sets the error code (HTTP status code)
diff --git a/modules/swagger-codegen/src/main/resources/csharp/ApiResponse.mustache b/modules/swagger-codegen/src/main/resources/csharp/ApiResponse.mustache
index d8c1b79e545..d04575d7ad9 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ApiResponse.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ApiResponse.mustache
@@ -7,7 +7,7 @@ namespace {{packageName}}.Client
     /// <summary>
     /// API Response
     /// </summary>
-    public class ApiResponse<T>
+    {{>visibility}} class ApiResponse<T>
     {
         /// <summary>
         /// Gets or sets the status code (HTTP status code)
diff --git a/modules/swagger-codegen/src/main/resources/csharp/Configuration.mustache b/modules/swagger-codegen/src/main/resources/csharp/Configuration.mustache
index 108b85e48f8..0e1856725df 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/Configuration.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/Configuration.mustache
@@ -11,7 +11,7 @@ namespace {{packageName}}.Client
     /// <summary>
     /// Represents a set of configuration settings
     /// </summary>
-    public class Configuration
+    {{>visibility}} class Configuration
     {
         /// <summary>
         /// Initializes a new instance of the Configuration class with different settings
diff --git a/modules/swagger-codegen/src/main/resources/csharp/ExceptionFactory.mustache b/modules/swagger-codegen/src/main/resources/csharp/ExceptionFactory.mustache
index c25b88ee614..f0ebb0b31ce 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ExceptionFactory.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ExceptionFactory.mustache
@@ -10,6 +10,6 @@ namespace {{packageName}}.Client
     /// </summary>
     /// <param name="methodName">Method name</param>
     /// <param name="response">Response</param>
-    /// <returns>Exceptions</returns>    
-    public delegate Exception ExceptionFactory(string methodName, IRestResponse response);
+    /// <returns>Exceptions</returns>
+    {{>visibility}} delegate Exception ExceptionFactory(string methodName, IRestResponse response);
 }
diff --git a/modules/swagger-codegen/src/main/resources/csharp/IApiAccessor.mustache b/modules/swagger-codegen/src/main/resources/csharp/IApiAccessor.mustache
index df236b8f8c8..290c9b6ffdc 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/IApiAccessor.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/IApiAccessor.mustache
@@ -11,7 +11,7 @@ namespace {{packageName}}.Client
     /// <summary>
     /// Represents configuration aspects required to interact with the API endpoints.
     /// </summary>
-    public interface IApiAccessor
+    {{>visibility}} interface IApiAccessor
     {
         /// <summary>
         /// Gets or sets the configuration object
diff --git a/modules/swagger-codegen/src/main/resources/csharp/api.mustache b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
index 18c949980cb..c3d73306149 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
@@ -14,7 +14,7 @@ namespace {{packageName}}.{{apiPackage}}
     /// <summary>
     /// Represents a collection of functions to interact with the API endpoints
     /// </summary>
-    public interface {{interfacePrefix}}{{classname}} : IApiAccessor
+    {{>visibility}} interface {{interfacePrefix}}{{classname}} : IApiAccessor
     {
         #region Synchronous Operations
         {{#operation}}
@@ -73,7 +73,7 @@ namespace {{packageName}}.{{apiPackage}}
     /// <summary>
     /// Represents a collection of functions to interact with the API endpoints
     /// </summary>
-    public partial class {{classname}} : {{interfacePrefix}}{{classname}}
+    {{>visibility}} partial class {{classname}} : {{interfacePrefix}}{{classname}}
     {
         private {{packageName}}.Client.ExceptionFactory _exceptionFactory = (name, response) => null;
 
diff --git a/modules/swagger-codegen/src/main/resources/csharp/enumClass.mustache b/modules/swagger-codegen/src/main/resources/csharp/enumClass.mustache
index 5249d754577..b11d14cdfc0 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/enumClass.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/enumClass.mustache
@@ -3,7 +3,7 @@
         /// </summary>{{#description}}
         /// <value>{{{description}}}</value>{{/description}}
         [JsonConverter(typeof(StringEnumConverter))]
-        public enum {{#datatypeWithEnum}}{{.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
+        {{>visibility}} enum {{#datatypeWithEnum}}{{.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
         {
             {{#allowableValues}}{{#enumVars}}
             /// <summary>
diff --git a/modules/swagger-codegen/src/main/resources/csharp/modelEnum.mustache b/modules/swagger-codegen/src/main/resources/csharp/modelEnum.mustache
index ff007904f46..b0dfa881eb2 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/modelEnum.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/modelEnum.mustache
@@ -3,7 +3,7 @@
     /// </summary>{{#description}}
     /// <value>{{{description}}}</value>{{/description}}
     [JsonConverter(typeof(StringEnumConverter))]
-    public enum {{#datatypeWithEnum}}{{.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
+    {{>visibility}} enum {{#datatypeWithEnum}}{{.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
     {
         {{#allowableValues}}{{#enumVars}}
         /// <summary>
diff --git a/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache b/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
index 5e1d0721dc2..09c232acefd 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/modelGeneric.mustache
@@ -5,7 +5,7 @@
     {{#generatePropertyChanged}}
     [ImplementPropertyChanged]
     {{/generatePropertyChanged}}
-    public partial class {{classname}} : {{#parent}}{{{parent}}}, {{/parent}} IEquatable<{{classname}}>, IValidatableObject
+    {{>visibility}} partial class {{classname}} : {{#parent}}{{{parent}}}, {{/parent}} IEquatable<{{classname}}>, IValidatableObject
     {
         {{#vars}}
         {{#isEnum}}
diff --git a/modules/swagger-codegen/src/main/resources/csharp/modelInnerEnum.mustache b/modules/swagger-codegen/src/main/resources/csharp/modelInnerEnum.mustache
index 855a710c7ed..d851a2dddc6 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/modelInnerEnum.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/modelInnerEnum.mustache
@@ -4,7 +4,7 @@
         /// </summary>{{#description}}
         /// <value>{{{description}}}</value>{{/description}}
         [JsonConverter(typeof(StringEnumConverter))]
-        public enum {{#datatypeWithEnum}}{{&.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
+        {{>visibility}} enum {{#datatypeWithEnum}}{{&.}}{{/datatypeWithEnum}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}
         {
             {{#allowableValues}}{{#enumVars}}
             /// <summary>
diff --git a/modules/swagger-codegen/src/main/resources/csharp/visibility.mustache b/modules/swagger-codegen/src/main/resources/csharp/visibility.mustache
new file mode 100644
index 00000000000..a1d1f4163d4
--- /dev/null
+++ b/modules/swagger-codegen/src/main/resources/csharp/visibility.mustache
@@ -0,0 +1 @@
+{{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}}
\ No newline at end of file
diff --git a/modules/swagger-codegen/src/test/java/io/swagger/codegen/csharp/CSharpClientOptionsTest.java b/modules/swagger-codegen/src/test/java/io/swagger/codegen/csharp/CSharpClientOptionsTest.java
index 8bc55f211be..195d928d8c6 100644
--- a/modules/swagger-codegen/src/test/java/io/swagger/codegen/csharp/CSharpClientOptionsTest.java
+++ b/modules/swagger-codegen/src/test/java/io/swagger/codegen/csharp/CSharpClientOptionsTest.java
@@ -50,6 +50,8 @@ public class CSharpClientOptionsTest extends AbstractOptionsTest {
             times = 1;
             clientCodegen.setGeneratePropertyChanged(true);
             times = 1;
+            clientCodegen.setNonPublicApi(true);
+            times = 1;
             clientCodegen.setInterfacePrefix("X");
             times = 1;
         }};
diff --git a/modules/swagger-codegen/src/test/java/io/swagger/codegen/options/CSharpClientOptionsProvider.java b/modules/swagger-codegen/src/test/java/io/swagger/codegen/options/CSharpClientOptionsProvider.java
index 9bbc6512911..833184775ba 100644
--- a/modules/swagger-codegen/src/test/java/io/swagger/codegen/options/CSharpClientOptionsProvider.java
+++ b/modules/swagger-codegen/src/test/java/io/swagger/codegen/options/CSharpClientOptionsProvider.java
@@ -35,6 +35,7 @@ public class CSharpClientOptionsProvider implements OptionsProvider {
                 .put(CodegenConstants.OPTIONAL_EMIT_DEFAULT_VALUES, "true")
                 .put(CodegenConstants.HIDE_GENERATION_TIMESTAMP, "true")
                 .put(CodegenConstants.GENERATE_PROPERTY_CHANGED, "true")
+                .put(CodegenConstants.NON_PUBLIC_API, "true")
                 .put(CodegenConstants.INTERFACE_PREFIX, "X")
                 .build();
     }