Crystalline solifenacin succinate, the solifenacin succinate having an average axial ratio of 5:1 or less, preferably an average axial ratio of 5:1 to 1:1, more preferably an average axial ratio of 1:1, and having at least one of the following properties: a) a particle size d 0.9 <； 200 µm； b) an average particle size of approximately 2 to 40 µm； and c) peaks in the X-ray powder diffractogram at 3.7； 11.1； 18.6； 21.8° 2? ± 0.2° 2?.
