Since the rise of internet and data transmission via public media, the security of information has become an important issue especially for the confidential data. Unfortunately; it is not enough sometimes to keep the contents of message secret, it may be also necessary to keep the existence of message secret. So cryptography and steganography can be combined to get this purpose. In this work, crypto-stego algorithm is proposed; which is based on both cryptography and steganography techniques. The proposed algorithm used Rivest- Shamir-Adleman (RSA) as a cryptographic algorithm to encrypt the secret message before hiding it in order to increase the security of the system. In addition, Integer Wavelet Transform (IWT) technique is utilized to embed the encrypted message in the frequency coefficients of the sub-bands. Finally, the proposed techniques obtained good results through satisfying and improving the most important properties of steganography such as: imperceptibility, security, and capacity.