Three-dimensional X-ray diffraction has been used to study the growth kinetics of 1406 individual grains recrystallizing in 50% cold-rolled aluminium. It is found that each grain follows its own kinetics. The radial growth of individual grains is found to often be piecewise linear, and an explanation based on the cell block microstructure of cold-rolled aluminium is proposed. Grain-averaged activation energies of 793 individual grains are determined, and found to constitute a broad distribution. Reasons and implications of these findings are discussed.