diff --git a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/Service.java b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/Service.java
index c3849a45f..970780714 100644
--- a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/Service.java
+++ b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/Service.java
@@ -2,11 +2,31 @@ package com.iluwatar.featuretoggle.pattern;
 
 import com.iluwatar.featuretoggle.user.User;
 
-
+/**
+ * Simple interfaces to allow the calling of the method to generate the welcome message for a given user. While there is
+ * a helper method to gather the the status of the feature toggle. In some cases there is no need for the
+ * {@link Service#isEnhanced()} in {@link com.iluwatar.featuretoggle.pattern.tieredversion.TieredFeatureToggleVersion}
+ * where the toggle is determined by the actual {@link User}.
+ *
+ * @see com.iluwatar.featuretoggle.pattern.propertiesversion.PropertiesFeatureToggleVersion
+ * @see com.iluwatar.featuretoggle.pattern.tieredversion.TieredFeatureToggleVersion
+ * @see User
+ */
 public interface Service {
 
+  /**
+   * Generates a welcome message for the passed user.
+   *
+   * @param user the {@link User} to be used if the message is to be personalised.
+   * @return Generated {@link String} welcome message
+   */
   String getWelcomeMessage(User user);
 
+  /**
+   * Returns if the welcome message to be displayed will be the enhanced version.
+   *
+   * @return Boolean {@value true} if enhanced.
+   */
   boolean isEnhanced();
 
 }
diff --git a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/propertiesversion/PropertiesFeatureToggleVersion.java b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/propertiesversion/PropertiesFeatureToggleVersion.java
index aa795b975..947efec6a 100644
--- a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/propertiesversion/PropertiesFeatureToggleVersion.java
+++ b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/propertiesversion/PropertiesFeatureToggleVersion.java
@@ -5,13 +5,21 @@ import com.iluwatar.featuretoggle.user.User;
 
 import java.util.Properties;
 
+/**
+ *
+ */
 public class PropertiesFeatureToggleVersion implements Service {
 
   private boolean isEnhanced;
 
   /**
+   * Creates an instance of {@link PropertiesFeatureToggleVersion} using the passed {@link Properties} to determine,
+   * the status of the feature toggle {@link PropertiesFeatureToggleVersion#isEnhanced()}. There is also some defensive
+   * code to ensure the {@link Properties} passed are as expected.
    *
    * @param properties {@link Properties} used to configure the service and toggle features.
+   * @throws IllegalArgumentException when the passed {@link Properties} is not as expected
+   * @see Properties
    */
   public PropertiesFeatureToggleVersion(final Properties properties) {
     if (properties == null) {
@@ -25,6 +33,18 @@ public class PropertiesFeatureToggleVersion implements Service {
     }
   }
 
+  /**
+   * Generate a welcome message based on the user being passed and the status of the feature toggle. If the enhanced
+   * version is enabled, then the message will be personalised with the name of the passed {@link User}. However if
+   * disabled then a generic version fo the message is returned.
+   *
+   * @param user the {@link User} to be displayed in the message if the enhanced version is enabled see
+   *             {@link PropertiesFeatureToggleVersion#isEnhanced()}. If the enhanced version is enabled, then the
+   *             message will be personalised with the name of the passed {@link User}. However if disabled then a
+   *             generic version fo the message is returned.
+   * @return Resulting welcome message.
+   * @see User
+   */
   @Override
   public String getWelcomeMessage(final User user) {
 
@@ -35,6 +55,13 @@ public class PropertiesFeatureToggleVersion implements Service {
     return "Welcome to the application.";
   }
 
+  /**
+   * Method that checks if the welcome message to be returned is the enhanced venison or not. For this service it will
+   * see the value of the boolean that was set in the constructor
+   * {@link PropertiesFeatureToggleVersion#PropertiesFeatureToggleVersion(Properties)}
+   *
+   * @return Boolean value {@value true} if enhanced.
+   */
   @Override
   public boolean isEnhanced() {
     return isEnhanced;
diff --git a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/tieredversion/TieredFeatureToggleVersion.java b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/tieredversion/TieredFeatureToggleVersion.java
index 2942618f1..a011b7b61 100644
--- a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/tieredversion/TieredFeatureToggleVersion.java
+++ b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/pattern/tieredversion/TieredFeatureToggleVersion.java
@@ -4,8 +4,22 @@ import com.iluwatar.featuretoggle.pattern.Service;
 import com.iluwatar.featuretoggle.user.User;
 import com.iluwatar.featuretoggle.user.UserGroup;
 
+/**
+ *
+ */
 public class TieredFeatureToggleVersion implements Service {
 
+  /**
+   * Generates a welcome message from the passed {@link User}. The resulting message depends on the group of the
+   * {@link User}. So if the {@link User} is in the {@link UserGroup#paidGroup} then the enhanced version of the
+   * welcome message will be returned where the username is displayed.
+   *
+   * @param user the {@link User} to generate the welcome message for, different messages are displayed if the user is
+   *             in the {@link UserGroup#isPaid(User)} or {@link UserGroup#freeGroup}
+   * @return Resulting welcome message.
+   * @see User
+   * @see UserGroup
+   */
   @Override
   public String getWelcomeMessage(User user) {
     if (UserGroup.isPaid(user)) {
@@ -15,6 +29,13 @@ public class TieredFeatureToggleVersion implements Service {
     return "I suppose you can use this software.";
   }
 
+  /**
+   * Method that checks if the welcome message to be returned is the enhanced version. For this instance as the logic
+   * is driven by the user group. This method is a little redundant. However can be used to show that there is an
+   * enhanced version available.
+   *
+   * @return Boolean value {@value true} if enhanced.
+   */
   @Override
   public boolean isEnhanced() {
     return true;
diff --git a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/user/UserGroup.java b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/user/UserGroup.java
index fec972eb1..2bdfcfdfc 100644
--- a/feature-toggle/src/main/java/com/iluwatar/featuretoggle/user/UserGroup.java
+++ b/feature-toggle/src/main/java/com/iluwatar/featuretoggle/user/UserGroup.java
@@ -19,7 +19,7 @@ public class UserGroup {
    * Add the passed {@link User} to the free user group list.
    *
    * @param user {@link User} to be added to the free group
-   * @throws IllegalArgumentException
+   * @throws IllegalArgumentException when user is already added to the paid group
    * @see User
    */
   public static void addUserToFreeGroup(final User user) throws IllegalArgumentException {
@@ -36,7 +36,7 @@ public class UserGroup {
    * Add the passed {@link User} to the paid user group list.
    *
    * @param user {@link User} to be added to the paid group
-   * @throws IllegalArgumentException
+   * @throws IllegalArgumentException when the user is already added to the free group
    * @see User
    */
   public static void addUserToPaidGroup(final User user) throws IllegalArgumentException {
@@ -49,6 +49,13 @@ public class UserGroup {
     }
   }
 
+  /**
+   * Method to take a {@link User} to determine if the user is in the {@link UserGroup#paidGroup}.
+   *
+   * @param user {@link User} to check if they are in the {@link UserGroup#paidGroup}
+   *
+   * @return true if the {@link User} is in {@link UserGroup#paidGroup}
+   */
   public static boolean isPaid(User user) {
     return paidGroup.contains(user);
   }