Do you need to encrypt sensitive data in PHP? Encryption is not enough, you need also authentication and data integrity! In this talk I will explain how to provide encryption using block ciphers, e.g. AES, and authentication plus data integrity using HMAC algorithms. We will talk about public key cryptography in PHP using OpenSSL, to provide digital signatures and watermarking techniques. Moreover, we will show some PHP examples using the zend-crypt component of Zend Framework that offers a simple and robust API for cryptographic scopes in PHP.