diff --git a/src/main/java/com/coscale/sdk/client/commons/Msg.java b/src/main/java/com/coscale/sdk/client/commons/Msg.java
index 349e488..0a24ced 100755
--- a/src/main/java/com/coscale/sdk/client/commons/Msg.java
+++ b/src/main/java/com/coscale/sdk/client/commons/Msg.java
@@ -2,7 +2,6 @@
 
 import javax.annotation.Nullable;
 
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Objects;
 
@@ -10,7 +9,6 @@
  * Msg is used to parse request responses that return a Status Message.
  *
  */
-@JsonIgnoreProperties({ "measurements" })
 public class Msg {
 
     @Nullable
diff --git a/src/main/java/com/coscale/sdk/client/metrics/MetricsApi.java b/src/main/java/com/coscale/sdk/client/metrics/MetricsApi.java
index d409609..8bf6b88 100755
--- a/src/main/java/com/coscale/sdk/client/metrics/MetricsApi.java
+++ b/src/main/java/com/coscale/sdk/client/metrics/MetricsApi.java
@@ -44,6 +44,8 @@ public List<Metric> all() throws IOException {
     /**
      * all is used to get a list of all metrics.
      * 
+     * @param options
+     *            filter the Metrics. e.g. filter by metric name.
      * @return List<Metric>
      * @throws IOException
      */
@@ -107,11 +109,27 @@ public List<MetricGroup> getAllMetricGroups() throws IOException {
                 });
     }
 
+    /**
+     * Get all metric groups.
+     * 
+     * @param options
+     *            filter the MetricGroups. e.g. filter by metric name.
+     * 
+     * @return List of all MetricGroups
+     * @throws IOException
+     */
+    public List<MetricGroup> getAllMetricGroups(Options options) throws IOException {
+        String url = "/metricgroups/";
+        url += (options.hasQuery() ? "?" : "&") + options.query();
+        return api.callWithAuth("GET", url, null, new TypeReference<List<MetricGroup>>() {
+        });
+    }
+
     /**
      * Get a specific metric group.
      * 
      * @param id
-     *            the id of the metric group
+     *            the id of the metric group.
      * @return MetricGroup
      * @throws IOException
      */
@@ -145,8 +163,9 @@ public MetricGroup insertMetricGroup(MetricGroupInsert metricGroup) throws IOExc
      * @throws IOException
      */
     public Msg deleteMetricGroup(long id) throws IOException {
-        return api.callWithAuth("DELETE", "/metricgroups/" + id + '/', null, new TypeReference<Msg>() {
-        });
+        return api.callWithAuth("DELETE", "/metricgroups/" + id + '/', null,
+                new TypeReference<Msg>() {
+                });
     }
 
     /**
@@ -154,12 +173,12 @@ public Msg deleteMetricGroup(long id) throws IOException {
      * 
      * @param childId
      * @param parentId
-     * @return MetricGroup: the added metric group.
+     * @return List of groups contained by the parent group.
      * @throws IOException
      */
-    public MetricGroup addGroupToGroup(long childId, long parentId) throws IOException {
+    public List<MetricGroup> addGroupToGroup(long childId, long parentId) throws IOException {
         return api.callWithAuth("POST", "/metricgroups/" + parentId + "/metricgroups/" + childId
-                + '/', null, new TypeReference<MetricGroup>() {
+                + '/', null, new TypeReference<List<MetricGroup>>() {
         });
     }
 
@@ -168,12 +187,12 @@ public MetricGroup addGroupToGroup(long childId, long parentId) throws IOExcepti
      * 
      * @param metricId
      * @param groupId
-     * @return Metric: the inserted metric.
+     * @return List of Metrics contained by the group.
      * @throws IOException
      */
-    public Metric addMetricToGroup(long metricId, long groupId) throws IOException {
+    public List<Metric> addMetricToGroup(long metricId, long groupId) throws IOException {
         return api.callWithAuth("POST", "/metricgroups/" + groupId + "/metrics/" + metricId + '/',
-                null, new TypeReference<Metric>() {
+                null, new TypeReference<List<Metric>>() {
                 });
     }
 
diff --git a/src/main/java/com/coscale/sdk/client/servers/ServerGroup.java b/src/main/java/com/coscale/sdk/client/servers/ServerGroup.java
new file mode 100644
index 0000000..aeb6df3
--- /dev/null
+++ b/src/main/java/com/coscale/sdk/client/servers/ServerGroup.java
@@ -0,0 +1,92 @@
+package com.coscale.sdk.client.servers;
+
+import java.util.List;
+
+import javax.annotation.Nullable;
+
+import com.coscale.sdk.client.metrics.State;
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
+
+public class ServerGroup {
+
+    @Nullable
+    public Long id;
+
+    @Nullable
+    public String source;
+
+    @Nullable
+    public List<Server> servers;
+
+    @Nullable
+    public String description;
+
+    @Nullable
+    public String name;
+
+    public State state;
+
+    @Nullable
+    public List<ServerGroup> servergroups;
+
+    @Nullable
+    public String type;
+
+    @Nullable
+    public Long version;
+
+    public ServerGroup(State state) {
+        this.state = state;
+    }
+
+    public ServerGroup(Long id, String source, List<Server> servers, String description,
+            String name, State state, List<ServerGroup> servergroups, String type, Long version) {
+        this.id = id;
+        this.source = source;
+        this.servers = servers;
+        this.description = description;
+        this.name = name;
+        this.state = state;
+        this.servergroups = servergroups;
+        this.type = type;
+        this.version = version;
+    }
+
+    public ServerGroup() {
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this).add("id", id).add("source", source)
+                .add("servers", servers).add("description", description).add("name", name)
+                .add("state", state).add("servergroups", servergroups).add("version", version)
+                .toString();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        final ServerGroup other = (ServerGroup) obj;
+
+        return Objects.equal(this.id, other.id) && Objects.equal(this.source, other.source)
+                && Objects.equal(this.servers, other.servers)
+                && Objects.equal(this.description, other.description)
+                && Objects.equal(this.name, other.name) && Objects.equal(this.state, other.state)
+                && Objects.equal(this.servergroups, other.servergroups)
+                && Objects.equal(this.type, other.type)
+                && Objects.equal(this.version, other.version);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(id, source, servers, description, name, state, servergroups, type,
+                version);
+    }
+
+}
\ No newline at end of file
diff --git a/src/main/java/com/coscale/sdk/client/servers/ServerGroupInsert.java b/src/main/java/com/coscale/sdk/client/servers/ServerGroupInsert.java
new file mode 100644
index 0000000..1a00829
--- /dev/null
+++ b/src/main/java/com/coscale/sdk/client/servers/ServerGroupInsert.java
@@ -0,0 +1,67 @@
+package com.coscale.sdk.client.servers;
+
+import javax.annotation.Nullable;
+
+import com.coscale.sdk.client.ApiClient;
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
+
+public class ServerGroupInsert {
+
+    public String name;
+
+    public String description;
+
+    public String type;
+
+    public String source;
+
+    @Nullable
+    public Long parentId;
+
+    public ServerGroupInsert(String name, String description, String type) {
+        this.name = name;
+        this.description = description;
+        this.type = type;
+        this.source = ApiClient.getSource();
+    }
+
+    public ServerGroupInsert(String name, String description, String type, Long parentId) {
+        this.name = name;
+        this.description = description;
+        this.type = type;
+        this.source = ApiClient.getSource();
+        this.parentId = parentId;
+    }
+
+    public ServerGroupInsert() {
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this).add("name", name).add("description", description)
+                .add("type", type).add("source", source).add("parentId", parentId).toString();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        final ServerGroupInsert other = (ServerGroupInsert) obj;
+
+        return Objects.equal(this.name, other.name)
+                && Objects.equal(this.description, other.description)
+                && Objects.equal(this.type, other.type) && Objects.equal(this.source, other.source)
+                && Objects.equal(this.parentId, other.parentId);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(name, description, type, source, parentId);
+    }
+
+}
\ No newline at end of file
diff --git a/src/main/java/com/coscale/sdk/client/servers/ServersApi.java b/src/main/java/com/coscale/sdk/client/servers/ServersApi.java
index 8cf8bb0..5f6d520 100755
--- a/src/main/java/com/coscale/sdk/client/servers/ServersApi.java
+++ b/src/main/java/com/coscale/sdk/client/servers/ServersApi.java
@@ -113,4 +113,167 @@ public Msg delete(long serverId) throws IOException {
                 new TypeReference<Msg>() {
                 });
     }
+
+    /** Server groups Calls */
+
+    /**
+     * Get all server groups.
+     * 
+     * @return List of all ServerGroups
+     * @throws IOException
+     */
+    public List<ServerGroup> getAllServerGroups() throws IOException {
+        return api.callWithAuth("GET", "/servergroups/", null,
+                new TypeReference<List<ServerGroup>>() {
+                });
+    }
+
+    /**
+     * Get all server groups.
+     * 
+     * @param options
+     *            filter the ServerGroups. e.g. filter by server name.
+     * 
+     * @return List of all ServerGroups
+     * @throws IOException
+     */
+    public List<ServerGroup> getAllServerGroups(Options options) throws IOException {
+        String url = "/servergroups/";
+        url += (options.hasQuery() ? "?" : "&") + options.query();
+        return api.callWithAuth("GET", url, null, new TypeReference<List<ServerGroup>>() {
+        });
+    }
+
+    /**
+     * Get a specific server group.
+     * 
+     * @param id
+     *            the id of the server group.
+     * @return ServerGroup
+     * @throws IOException
+     */
+    public ServerGroup getServerGroup(long id) throws IOException {
+        return api.callWithAuth("GET", "/servergroups/" + id + '/', null,
+                new TypeReference<ServerGroup>() {
+                });
+    }
+
+    /**
+     * Insert a new server group. Optionally set which ServerGroup will be its
+     * parent (this is set in ServerGroupInsert object).
+     * 
+     * @param serverGroup
+     *            the server group to insert.
+     * @return ServerGroup
+     * @throws IOException
+     */
+    public ServerGroup insertServerGroup(ServerGroupInsert serverGroup) throws IOException {
+        return api.callWithAuth("POST", "/servergroups/", serverGroup,
+                new TypeReference<ServerGroup>() {
+                });
+    }
+
+    /**
+     * Delete a specific server group.
+     * 
+     * @param id
+     *            the id of the server group.
+     * @return Msg
+     * @throws IOException
+     */
+    public Msg deleteServerGroup(long id) throws IOException {
+        return api.callWithAuth("DELETE", "/servergroups/" + id + '/', null,
+                new TypeReference<Msg>() {
+                });
+    }
+
+    /**
+     * Add an existing server group to another server group.
+     * 
+     * @param childId
+     * @param parentId
+     * @return List of groups contained by the parent group.
+     * @throws IOException
+     */
+    public List<ServerGroup> addGroupToGroup(long childId, long parentId) throws IOException {
+        return api.callWithAuth("POST", "/servergroups/" + parentId + "/servergroups/" + childId
+                + '/', null, new TypeReference<List<ServerGroup>>() {
+        });
+    }
+
+    /**
+     * Add an existing server to a server group.
+     * 
+     * @param serverId
+     * @param groupId
+     * @return List of Server contained by the group.
+     * @throws IOException
+     */
+    public List<Server> addServerToGroup(long serverId, long groupId) throws IOException {
+        return api.callWithAuth("POST", "/servergroups/" + groupId + "/servers/" + serverId + '/',
+                null, new TypeReference<List<Server>>() {
+                });
+    }
+
+    /**
+     * * Get all servers in the server group.
+     * 
+     * @param groupId
+     *            the id of the server group.
+     * @return List of Server.
+     * @throws IOException
+     */
+    public List<Server> getGroupServers(long groupId) throws IOException {
+        return api.callWithAuth("GET", "/servergroups/" + groupId + "/servers/", null,
+                new TypeReference<List<Server>>() {
+                });
+    }
+
+    /**
+     * Delete a server from a server group.
+     * 
+     * @param serverId
+     *            the id of the server.
+     * @param groupId
+     *            the id of the group.
+     * @return Msg.
+     * @throws IOException
+     */
+    public Msg deleteServerFromGroup(long serverId, long groupId) throws IOException {
+        return api.callWithAuth("DELETE",
+                "/servergroups/" + groupId + "/servers/" + serverId + '/', null,
+                new TypeReference<Msg>() {
+                });
+    }
+
+    /**
+     * Get all child server groups for a server group.
+     * 
+     * @param groupId
+     *            the if of the group.
+     * @return List of ServerGroup.
+     * @throws IOException
+     */
+    public List<ServerGroup> getGroupsFromGroup(long groupId) throws IOException {
+        return api.callWithAuth("GET", "/servergroups/" + groupId + "/servergroups/", null,
+                new TypeReference<List<ServerGroup>>() {
+                });
+    }
+
+    /**
+     * Delete a server group from another server group.
+     * 
+     * @param childId
+     *            the id of the group that will be removed.
+     * @param parentId
+     *            the id of the group from which the child group will be
+     *            removed.
+     * @return Msg.
+     * @throws IOException
+     */
+    public Msg deleteGroupFromGroup(long childId, long parentId) throws IOException {
+        return api.callWithAuth("DELETE", "/servergroups/" + parentId + "/servergroups/" + childId
+                + '/', null, new TypeReference<Msg>() {
+        });
+    }
 }
diff --git a/src/main/java/com/coscale/sdk/client/utils/MapperSupport.java b/src/main/java/com/coscale/sdk/client/utils/MapperSupport.java
index 75dedf0..f404262 100755
--- a/src/main/java/com/coscale/sdk/client/utils/MapperSupport.java
+++ b/src/main/java/com/coscale/sdk/client/utils/MapperSupport.java
@@ -1,6 +1,7 @@
 package com.coscale.sdk.client.utils;
 
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
+import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 public class MapperSupport {
@@ -19,6 +20,9 @@ private static class Keeper {
 
         private static ObjectMapper configure(ObjectMapper mapper) {
             mapper.setSerializationInclusion(Include.NON_NULL);
+            
+            // Ignore Unknown fiels.
+            mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
             return mapper;
         }
     }