A new method of compression-arthrodesis of the ankle joint using monolateral external fixation is introduced. After bimalleolar incision and resection of the tibio-talar joint-surfaces, compression fixation was achieved by the Monofixateur placed ventromedially. The lateral malleolus was used as a bar-chip fixed with two screws. Between 1985 and 1988 this operation was performed on ten patients, mostly because of posttraumatic joint destruction. On the average the hospital stay was 17 days. Walking with crutches was allowed on the third postop. day with partial weight bearing after one week. Two patients developed a pin-tract infection with one of them needing operative revision. Except in a case of primary arthrodesis done in a severely open talus dislocation fracture bony fusion was achieved between 8 to 12 weeks postoperatively. Eight patients were followed up after an average of 2.5 years. Four patients were completely painfree and showed an almost normal gait. Four patients were able to walk 2 to 3 hours without serious complains. Five patients classified the result as good, two as fair and one as poor. In the poor result the distal Schanz-screws had partially penetrated the subtalar joint with consecutive joint deterioration. The tarsal mobility had a mean value of 23 degrees. The length of the operated leg was on the average one cm shorter. Due to the favourable results we recommend monolateral external compression-arthrodesis as a useful procedure.