Digital rights management of audio signals through robust watermarking has received significant attention during the last years. Two approaches for blind robust watermarking of audio signals are presented in this chapter. Both approaches use chaotic maps for the generation of the watermark signals and a correlation-based watermark detection procedure. The first method is a zero-bit method that embeds high-frequency chaotic watermarks in the low frequencies of the Discrete Fourier Transform (DFT) domain, thus achieving reliable detection and robustness to a number of attacks. The second method operates on the temporal domain and robustly embeds multiple bits of information in the host signal. Experimental results are provided to demonstrate the performance of the two methods.