More than 20 years ago, the Human Genome Project mapped the genes that make us who we are, paving the way for using information about an individual's genes in health care. 'Pharmacogenomics' studies how our genes influence our response to medicines. We know that differences in the genes that respond to medicines mean that a medicine can work well in some, fail to work in others, or cause serious side effects. Pharmacogenomics knowledge is at a stage where it can benefit people in the clinic. Unfortunately the lack of clear rules around where and how pharmacogenomics should be used is slowing its uptake in the NHS and discouraging investment in new pharmacogenomics work. Pharmacogenomics means moving from a 'one dose fits all' approach to prescribing medicines, to a totally different approach where the type of medicine and its dose is influenced by a genetic test. This raises many challenges: * Government organisations on medicines regulations will need the evidence to show that the pharmacogenomics approach is safe and benefits patients and to create new instructions for the box of every drug where pharmacogenomics is important. * Regulators will need to create rules ensuring fair access to genetic testing. * Most genomic information in the UK is from people of White British ancestry; more work will be needed with ethnic minorities to avoid making race inequalities worse. * Healthcare workers and regulators will need training in this new form of prescribing. * Regulators will need to create rules on whether and how artificial intelligence can be used to guide prescribing. * Our health records must be able to record genomic information reliably in a way that can be shared with general practitioners and specialists. * The NHS will need to work with companies to make genomic testing value for money. * We will need to move from individual genetic tests taken when someone is ill, to testing the healthy population to save money. We aim to create a network of scientists from universities and industry, healthcare professionals and government to tackle these problems. In this first development phase, the network will hold 5 workshops to understand and plan the work needed to overcome these challenges. Ultimately, if successful in the next stage, our network will work with regulators and the NHS to develop sensible and practical guidelines for using pharmacogenomics in the NHS. This will enable patients to benefit and make pharmacogenomics a more attractive area for innovation.