A data-collection method for macromolecular crystals using convergent sources is described here. Because of the unique characteristics of the diffraction patterns, a software package CBMPRO has been developed speci®cally for processing data images collected with the convergent beam method (CBM). The resulting data sets from crystals with two different sets of unit-cell parameters are presented and compared. There is good agreement between data sets from the same type of crystals under slightly different experimental conditions and data sets collected and processed with CBM also agree well with those from conventional oscillation methods, marking an important step to establishing CBM as a viable alternate datacollection method for macromolecular crystals.