Dear Colleagues, On behalf of the PTCOG Executive Committee and the Local Organizing Committee, it is my great pleasure to invite you to Buenos Aires, Argentina, for the 63rd Annual Conference of the Particle Therapy Cooperative Group (PTCOG 63), taking place from 2-7 June 2025. This is a particularly special event as it marks the first time PTCOG organizes the Annual Conference in South America. It will be hosted in Argentina, and we are thrilled to be here during a pivotal moment for the region with the opening of Argentina's first Proton Therapy Centre. Buenos Aires, a vibrant city known for its rich culture, will serve as the perfect backdrop for our conference. As we gather to share the latest advancements and foster new collaborations in particle therapy, we hope this meeting will inspire and impact the growth of particle therapy in Latin America. We highly encourage the participation of colleagues from across Central and South America at PTCOG 63, where we will have dedicated sessions in Spanish, overcoming language barriers and promoting successful interaction between peers from the Latin American countries. This will provide an important opportunity for participants from the region to engage more deeply, access global knowledge, strengthen regional cooperation, and contribute to the broader exchange of expertise in particle therapy. Time: 9:00 AM - 8:00 PM