A convertible chair adapted for conversion between a sitting configuration and a kneeling configuration includes_a base support, a knee-back rest movably coupled to the base support by a pivot arm, a seat movably coupled to the base support by a coupling mechanism, and a connecting arm linking the pivot arm and the seat. The seat is arranged to move relative to the base support between a first seat position corresponding to the sitting configuration and a second seat position corresponding to the kneeling configuration. The pivot arm is arranged to pivot relative to the base support between a first pivot arm position in which the knee-back rest is in a first knee-back rest position for use as a back rest and a second pivot arm position in which the knee-back rest is in a second knee-back rest position for use as a knee rest.