A review is given of finite element methods of analysing uniform waveguide as used in microwaves and optics, with emphasis on the latter. The main concern is with modal analysis of the waveguides, such as to give the dominant few modes of any prescribed waveguide structure. Spurious modes are considered, with two recently successful schemes for their avoidance. Attention is also drawn to the commonly ignored 'complex modes'. Modal analysis of these same optical waveguides, but including non-linear material, is considered. Z-stepping algorithms are referred to for their importance in dealing with non-linear waveguides, and with slowly varying, long, guiding structures.