This chapter generally categorizes the channel assignment schemes as contention-free and contention-based channel assignment schemes, depending on the nature of ad hoc environments. It presents a new classification of the channel assignment schemes for Mobile ad hoc network (MANET), in which the allocation strategies are classified in two main categories: contention-free and contention-based channel assignment schemes. These schemes can be classified as the contention-free (Fixed channel assignment (FCA) schemes, On-demand channel assignment (ODCA) schemes) and contention-based channel assignment schemes. The chapter gives an overview of the most basic heuristics for fixed-channel assignment. It provides an in-depth survey of the most recent channel assignment schemes for wireless ad hoc networks. The intelligent bandwidth allocation schemes are the promising approaches that are opening the new horizons to the researchers to design efficient radio channel assignment protocols.