Douglas Instruments 1 article published in JoVE Biology Improving the Success Rate of Protein Crystallization by Random Microseed Matrix Screening Marisa Till1, Alice Robson1, Matthew J. Byrne1, Asha V. Nair1, Stefan A. Kolek2, Patrick D. Shaw Stewart2, Paul R. Race1 1School of Biochemistry, University of Bristol, 2Douglas Instruments Here we describe a general method for random microseed matrix screening. This technique is shown to significantly increase the success rate of protein crystallization screening experiments, reduce the need for optimization, and provide a reliable supply of crystals for data collection and ligand-soaking experiments.