How does medicine work? How are new drugs made? What role does the pharmaceutical industry play? Professors Stefan Knapp and Chas Bountra work in the field of drug discovery. They joined Science Oxford talks in spring 2013. Over the past 30 to 40 years there have been drastic changes in the way new medicines are developed. Before the 1970s drug development was based on phenotypic assays and 'accidental findings', with an approval process that would often take two to three years to complete. Scientists now have a better understanding of the mechanisms leading to disease development, allowing the selection of 'targets' - regulators which are dysfunctional in the disease - allowing scientists to develop new drugs, which inhibit these cellular targets.