DiscussionThe direct label free measurement of substrate to product conversion in both biochemical and cellular assays is probably considered the "Holy Grail" of screening. Mass Spectrometry has the potential to be the end point of this particular quest. This presentation will review current applications of MS screening within early drug discovery at AstraZeneca and share case study data to demonstrate the impact of MS screening. AZ is looking to new technologies which offer potential solutions to the current challenges of using MS as a screening end point. In particular, applications for MALDI and other soft ionisation techniques and the use of acoustic technology to address throughput bottlenecks.