Public payers and pharmaceutical manufacturers have a shared interest in enabling timely access to necessary and innovative medicines. At the same time, there is a tension between the interests of purchasers (to contain costs) and of manufacturers (to provide return on investment and maximize profits). The most common pricing mechanisms in Europe – such as external reference pricing (ERP) and managed entry agreements (MEAs) – tend to create incentives for pharmaceutical companies to give confidential discounts on the official list prices. This obscures the actual prices paid for medicines. Net price transparency (NPT) for pharmaceuticals – the public disclosure of prices paid to manufacturers – is seen by many as key to overcoming the opacity of pharmaceutical systems and to addressing the imbalance between countries with different levels of negotiating power (as larger or smaller purchasers, or richer or poorer countries). It is also regarded as a means of ensuring that public payers purchasing pharmaceuticals for their populations can be held accountable. However, policy action on NPT is not straightforward: Empirical evidence on the effect of NPT is extremely limited. Economic simulations do not provide a clear answer and evidence from natural experiments only comes from very specific settings, not least because NPT policies have never been fully implemented. Some policy-makers are concerned that moves towards increased price transparency would have a negative impact on accessibility, because pharmaceutical companies may then withdraw from markets or set prices at unaffordable levels, in particular in cases of less attractive (e.g. smaller) markets. Payers in different health systems may consider measures to increase price transparency for pharmaceuticals as more or less necessary to increase affordable access to medicines. Any movement towards NPT requires a re-examination of the established trade-offs in pharmaceutical policy in Europe and worldwide. It is important to consider: the differing needs and negotiating capacities across countries; the complexities of the interactions between stakeholders; the particularities of specific market segments; the way the process of implementation may shape the policy’s impact; the consequences for different countries and the ‘knock on’ implications of these effects for availability and affordability in other (national) health systems; the likely implications for innovation. Increasing transparency in the pharmaceutical system will require greater European and international collaboration – strengthening and going beyond existing initiatives. It also demands a clear focus on maintaining access, innovation and sustainability. Recent experience with joint purchasing, such as in the case of the COVID-19 vaccines, may bolster similar initiatives in future.