As the COVID-19 pandemic illustrated, vaccines play a really important part in controlling infectious diseases. If scientists work together across the world, then greater progress can be made than if they work alone. VALIDATE is a network which aims to speed up vaccine development for three groups of bugs that are difficult to design vaccines for and which cause a lot of disease and death across the world, particularly in low income countries. These diseases often do not attract lots of research and development funding, in part because they primarily affect poor people who cannot pay for expensive vaccines. VALIDATE started in 2017 and has grown from 32 founding members to now having more than 500 members around the world. Over the last five years we have supported the career development of many of our members and have also funded many small projects - some of which have led on to much bigger projects being funded by the MRC and other global funders. We now want to secure funding for the next four years so we can carry on supporting vaccine research and the careers of people working in vaccine development. Our chosen groups of bugs, which cause diseases like tuberculosis (TB), are similar in how the body responds to them. They are all very good at hiding from the immune system - which means they can stay hidden in the body and cause disease much later in life. They also need similar types of immune responses for the body to be able to get rid of them. In this network, we will do two things: 1. Provide small pots of funding for our members to perform research which will help us understand how best to develop vaccines for these difficult bugs. 2. Provide training and a supportive environment to encourage young scientists to stay working in this field. We will have a network meeting every year where our members can come and present their data and meet other scientists working in the field. We will host regular talks, which will be online to allow more people to join, particularly from lower income countries. We will offer opportunities for young scientists to have training in other laboratories, and will provide mentoring to support young scientists in their careers. We will work with schools to increase knowledge of these bugs. Overall, in this network, we aim to support vaccine development and also support the careers of people working in this field.