Methods and apparatus are provided for clock domain conversion in digital processing systems. The methods include operating a first circuit in a fast clock domain with a fast clock and operating a second circuit in a slow clock domain with a slow clock. To transfer signals from the fast clock domain to the slow clock domain, a first synchronization signal is asserted during each fast clock cycle in which a slow clock edge occurs. A fast signal is transferred from the fast clock domain to the slow clock domain on a fast clock edge when the first synchronization signal is asserted. To transfer signals from the slow clock domain to the fast clock domain, a second synchronization signal is asserted during each fast clock cycle that immediately follows a slow clock edge. A slow signal is transferred from the slow clock domain to the fast clock domain on a fast clock edge when the second synchronization signal is asserted.