diff --git a/src/main/java/com/launchdarkly/client/LDUser.java b/src/main/java/com/launchdarkly/client/LDUser.java
index 6dc26e836..b3edb2f9f 100644
--- a/src/main/java/com/launchdarkly/client/LDUser.java
+++ b/src/main/java/com/launchdarkly/client/LDUser.java
@@ -2,8 +2,10 @@
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.gson.Gson;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
 import com.google.gson.TypeAdapter;
 import com.google.gson.internal.Streams;
@@ -14,6 +16,8 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -143,6 +147,32 @@ JsonElement getCustom(String key) {
     return null;
   }
 
+  JsonObject toJsConfig(LDConfig config) {
+    JsonElement tree = new Gson().toJsonTree(this);
+
+    Set<String> privateAttributeSet = new HashSet<>();
+    privateAttributeSet.addAll(this.privateAttributeNames);
+    privateAttributeSet.addAll(config.privateAttrNames);
+
+    List<String> attrs = new ArrayList<>();
+    attrs.addAll(privateAttributeSet);
+    Collections.sort(attrs);
+
+    JsonArray array = new JsonArray();
+    for (String element : attrs) {
+      array.add(new JsonPrimitive(element));
+    }
+
+    JsonObject object = tree.getAsJsonObject();
+    object.add("privateAttributeNames", array);
+
+    if (config.allAttributesPrivate) {
+      object.addProperty("allAttributesPrivate", true);
+    }
+
+    return object;
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;
diff --git a/src/test/java/com/launchdarkly/client/LDUserTest.java b/src/test/java/com/launchdarkly/client/LDUserTest.java
index ca8a9f7f4..58d146b16 100644
--- a/src/test/java/com/launchdarkly/client/LDUserTest.java
+++ b/src/test/java/com/launchdarkly/client/LDUserTest.java
@@ -92,6 +92,56 @@ public void testInvalidCountryNameDoesNotSetCountry() {
     assert(user.getCountry() == null);
   }
 
+  @Test
+  public void testLDUserJsConfig() {
+    LDConfig config = LDConfig.DEFAULT;
+    LDUser user = new LDUser.Builder("key")
+            .privateCustom("private-key", "private-value")
+            .custom("public-key", "public-value")
+            .build();
+
+    JsonObject object = user.toJsConfig(config);
+
+    assertEquals("key", object.get("key").getAsString());
+
+    JsonArray privateAttributeNames = object.get("privateAttributeNames").getAsJsonArray();
+    assertEquals(1, privateAttributeNames.size());
+    assertEquals("private-key", privateAttributeNames.get(0).getAsString());
+
+    assertEquals("private-value", object.get("custom").getAsJsonObject().get("private-key").getAsString());
+    assertEquals("public-value", object.get("custom").getAsJsonObject().get("public-key").getAsString());
+  }
+
+  @Test
+  public void testLDUserJsConfigAllAttributesPrivate() {
+    LDConfig config = new LDConfig.Builder()
+            .allAttributesPrivate(true)
+            .build();
+    LDUser user = new LDUser.Builder("key")
+            .build();
+
+    JsonObject object = user.toJsConfig(config);
+
+    assertTrue(object.get("allAttributesPrivate").getAsBoolean());
+  }
+
+  @Test
+  public void testLDUserJsConfigPrivate() {
+    LDConfig config = new LDConfig.Builder()
+            .privateAttributeNames("private-key")
+            .build();
+    LDUser user = new LDUser.Builder("key")
+            .privateCustom("private-key2", "private-value2")
+            .build();
+
+    JsonObject object = user.toJsConfig(config);
+
+    JsonArray privateAttributeNames = object.get("privateAttributeNames").getAsJsonArray();
+    assertEquals(2, privateAttributeNames.size());
+    assertEquals("private-key", privateAttributeNames.get(0).getAsString());
+    assertEquals("private-key2", privateAttributeNames.get(1).getAsString());
+  }
+
   @Test
   public void testLDUserJsonSerializationContainsCountryAsTwoDigitCode() {
     LDConfig config = LDConfig.DEFAULT;