A configurable wavelength-selective cross-connect (WSXC) device having an array of optical ports in which at least some of the ports are configurable to operate as common ports or as plural ports. The configurable WSXC device includes a MEMS mirror array whose mirrors are tiltable in a manner that enables, e.g., reconfigurations of the configurable WSXC device that result in a change of the number of common ports therein. In one possible configuration, the configurable WSXC device can operate as 1×M1 wavelength-selective switch, where M1+1≦P, and P is the total number of optical ports in the array of optical ports. In another possible configuration, the configurable WSXC device can operate as a bank of n 1×M2 wavelength-selective switches, where n is a positive integer greater than one, and n(M2+1)≦P.