This study proposes for the first time a directional modulation (DM) transmitter constructed using a circular array. The mode patterns, generated with the help of a Fourier transform network, are exploited in order to synthesis information patterns and orthogonal interference patterns, which enable the required DM functionality. The design procedures are presented, and example simulation results are provided. When compared with its linear DM counterpart, the proposed circular DM system exhibits enhanced secrecy performance.