The absorption and transformation of electromagnetic waves in the vicinity of electron cyclotron harmonics is considered. The results of a simple WKB theory and a full wave theory are compared. It is found that for waves perpendicularly incident on a resonant surface (where the wave frequency equals an integer multiple of the electron cyclotron frequency), the full wave treatment is necessary to determine reflection and mode conversion coefficients, whereas, the WKB theory and full wave theory predict the same transmission coefficient. As the angle of incidence is decreased from 90°, the reflection and mode conversion coefficients become unimportant so that the full wave theory and WKB theory agree. The relevance of these processes to the heating of toroidal plasmas with high frequency waves is discussed.