diff --git a/Sources/ElevenLabsSwift/ElevenLabsSwift.swift b/Sources/ElevenLabsSwift/ElevenLabsSwift.swift
index 3a57131..fb0edcf 100644
--- a/Sources/ElevenLabsSwift/ElevenLabsSwift.swift
+++ b/Sources/ElevenLabsSwift/ElevenLabsSwift.swift
@@ -5,7 +5,7 @@ import os.log
 
 /// Main class for ElevenLabsSwift package
 public class ElevenLabsSDK {
-    public static let version = "1.0.0"
+    public static let version = "1.0.1"
 
     private enum Constants {
         static let defaultApiOrigin = "wss://api.elevenlabs.io"
@@ -18,6 +18,80 @@ public class ElevenLabsSDK {
         static let bufferSize: AVAudioFrameCount = 1024
     }
 
+    // MARK: - Session Config Utilities
+
+    public enum Language: String, Codable, Sendable {
+        case en, ja, zh, de, hi, fr, ko, pt, it, es, id, nl, tr, pl, sv, bg, ro, ar, cs, el, fi, ms, da, ta, uk, ru, hu, no, vi
+    }
+
+    public struct AgentPrompt: Codable, Sendable {
+        public var prompt: String?
+
+        public init(prompt: String? = nil) {
+            self.prompt = prompt
+        }
+    }
+
+    public struct TTSConfig: Codable, Sendable {
+        public var voiceId: String?
+
+        private enum CodingKeys: String, CodingKey {
+            case voiceId = "voice_id"
+        }
+
+        public init(voiceId: String? = nil) {
+            self.voiceId = voiceId
+        }
+    }
+
+    public struct ConversationConfigOverride: Codable, Sendable {
+        public var agent: AgentConfig?
+        public var tts: TTSConfig?
+
+        public init(agent: AgentConfig? = nil, tts: TTSConfig? = nil) {
+            self.agent = agent
+            self.tts = tts
+        }
+    }
+
+    public struct AgentConfig: Codable, Sendable {
+        public var prompt: AgentPrompt?
+        public var firstMessage: String?
+        public var language: Language?
+
+        private enum CodingKeys: String, CodingKey {
+            case prompt
+            case firstMessage = "first_message"
+            case language
+        }
+
+        public init(prompt: AgentPrompt? = nil, firstMessage: String? = nil, language: Language? = nil) {
+            self.prompt = prompt
+            self.firstMessage = firstMessage
+            self.language = language
+        }
+    }
+
+    public enum LlmExtraBodyValue: Codable, Sendable {
+        case string(String)
+        case number(Double)
+        case boolean(Bool)
+        case null
+        case array([LlmExtraBodyValue])
+        case dictionary([String: LlmExtraBodyValue])
+
+        var jsonValue: Any {
+            switch self {
+            case let .string(str): return str
+            case let .number(num): return num
+            case let .boolean(bool): return bool
+            case .null: return NSNull()
+            case let .array(arr): return arr.map { $0.jsonValue }
+            case let .dictionary(dict): return dict.mapValues { $0.jsonValue }
+            }
+        }
+    }
+
     // MARK: - Audio Utilities
 
     public static func arrayBufferToBase64(_ data: Data) -> String {
@@ -113,15 +187,21 @@ public class ElevenLabsSDK {
     public struct SessionConfig: Sendable {
         public let signedUrl: String?
         public let agentId: String?
+        public let overrides: ConversationConfigOverride?
+        public let customLlmExtraBody: [String: LlmExtraBodyValue]?
 
-        public init(signedUrl: String) {
+        public init(signedUrl: String, overrides: ConversationConfigOverride? = nil, customLlmExtraBody: [String: LlmExtraBodyValue]? = nil) {
             self.signedUrl = signedUrl
             agentId = nil
+            self.overrides = overrides
+            self.customLlmExtraBody = customLlmExtraBody
         }
 
-        public init(agentId: String) {
+        public init(agentId: String, overrides: ConversationConfigOverride? = nil, customLlmExtraBody: [String: LlmExtraBodyValue]? = nil) {
             self.agentId = agentId
             signedUrl = nil
+            self.overrides = overrides
+            self.customLlmExtraBody = customLlmExtraBody
         }
     }
 
@@ -157,6 +237,25 @@ public class ElevenLabsSDK {
             let socket = session.webSocketTask(with: url)
             socket.resume()
 
+            // Always send initialization event
+            var initEvent: [String: Any] = ["type": "conversation_initiation_client_data"]
+
+            // Add overrides if present
+            if let overrides = config.overrides,
+               let overridesDict = overrides.dictionary
+            {
+                initEvent["conversation_config_override"] = overridesDict
+            }
+
+            // Add custom body if present
+            if let customBody = config.customLlmExtraBody {
+                initEvent["custom_llm_extra_body"] = customBody.mapValues { $0.jsonValue }
+            }
+
+            let jsonData = try JSONSerialization.data(withJSONObject: initEvent)
+            let jsonString = String(data: jsonData, encoding: .utf8)!
+            try await socket.send(.string(jsonString))
+
             let configData = try await receiveInitialMessage(socket: socket)
             return Connection(socket: socket, conversationId: configData.conversationId, sampleRate: configData.sampleRate)
         }
@@ -1012,3 +1111,10 @@ private extension Data {
         self = buffer.withUnsafeBufferPointer { Data(buffer: $0) }
     }
 }
+
+extension Encodable {
+    var dictionary: [String: Any]? {
+        guard let data = try? JSONEncoder().encode(self) else { return nil }
+        return (try? JSONSerialization.jsonObject(with: data, options: .allowFragments)) as? [String: Any]
+    }
+}