Medications are widely used to treat and prevent debilitating and fatal diseases. Over 73% of Canadians over the age of 65 use at least one prescription medication daily. As a result, adverse drug events (ADEs)-the harmful and unintended consequences of medications-are common, and cause 1.7 million emergency department visits in Canada each year. Many ADEs occur because patients are re-exposed to drugs that have previously caused problems, because information about ADEs is not effectively communicated between healthcare providers (e.g. between physicians and pharmacists) or across healthcare sectors (e.g. between hospitals and community pharmacies). We have partnered with a broad range of stakeholders to design a new ADE reporting platform in PharmaNet, BC's provincial medication information system, so that front-line clinicians can communicate relevant ADE information between healthcare providers and across healthcare sectors. We will use this platform to collect data about ADEs for research and decision-making. First, we will determine how a new electronic ADE reporting platform can be integrated into the existing workflow of emergency department healthcare workers. Second, we will determine what information needs to be captured so that the ADE reports are sufficiently detailed to support clinical decisions. Then, we will develop and implement an electronic ADE reporting platform, and will develop computerized alerts that pop up when physicians or pharmacists prescribe or dispense medications that have previously caused problems. Finally, we will evaluate the ADE reports in PharmaNet. The new ADE reporting platform has a strong potential to make prescribing decisions safer, by warning healthcare providers of medications that have previously caused problems. By creating ADE reports that can be linked to other health data, we will support the data needs of researchers and decision makers to influence health programs and policy decisions.