The discrete cosine transform is proposed as a basis for representing fundamental frequency (F0) contours of speech. The advantages over existing representations include deterministic algorithms for both analysis and synthesis and a simple distance measure in the parameter space. A two-tier model using the DCT is shown to be able to model F0 contours to around 10 Hz RMS error. A proof-of-concept system for synthesising DCT parameters is evaluated, showing that the benefits do not come at the expense of speech synthesis applications.