The present invention provides a strictly non-blocking WDM cross-connect that utilizes a relatively small number of wavelength interchangers. In accordance with one embodiment, the WDM cross-connect utilizes n.sub.1 k.sub.1 wavelength interchangers, where n.sub.1 is an integer equal to the number of wavelengths carried on an input optical fiber associated with the WDM cross-connect and k.sub.1 is the total number of input optical fibers to the WDM cross-connect. Each of the wavelength interchangers is connected to exactly one input port of the fabric and each input port of the fabric is connected to exactly one wavelength interchanger. The input optical fibers of the WDM cross-connect are connected to k.sub.1 optical switches of the cross-connect that separate out the n.sub.1 wavelengths onto n.sub.1 optical fibers, which are input to respective wavelength interchangers. Therefore, each wavelength interchanger receives exactly n.sub.1 optical fibers. The fabric has output ports that are connected to k.sub.2 output optical fibers, where k.sub.2 is an integer equal to the number of output optical fibers that are connected to the output ports of the fabric. In accordance with another embodiment of the present invention, the WDM cross-connect comprises two fabrics and one or more wavelength interchangers that interconnect the fabrics. The cross-connect in accordance with this embodiment can be rendered strictly non-blocking by utilizing a number of wavelength interchangers equal to (k.sub.1 +k.sub.2)-1, where k.sub.1 and k.sub.2 correspond to the number of input and output optical fibers, respectively, of the WDM cross-connect. In accordance with both of these embodiments, the number of input and output optical fibers of the strictly non-blocking WDM cross-connect can be unequal.