Casa Pia Atlético Clube, commonly known as Casa Pia AC, is a Portuguese multi-sport club based in Lisbon, Portugal. Officially founded on 3 July 1920, the club has historical roots connected to the football team formed at the Casa Pia de Lisboa institution in 1893. This early team achieved an important milestone in Portuguese football by defeating the English-associated Carcavellos Club in 1898, helping popularise the sport in the country. Casa Pia AC has since developed into an established sporting institution, best known for its professional men's football team, which competes in Portugal's top professional division. The club is nicknamed “Os Gansos,” meaning “The Geese,” and is traditionally associated with black and white colours. Its home ground is Estádio Pina Manique in Lisbon, named after the historical figure associated with the Casa Pia institution. The club has a distinctive place in Portuguese football history, having participated in the inaugural season of the national first division in 1938–39. After spending many decades outside the top flight, Casa Pia secured promotion to the Primeira Liga in 2022, returning to Portugal's highest level after an absence of more than eight decades. Alongside its senior men's team, the organisation maintains youth football development programmes designed to identify and nurture emerging players through structured coaching and competitive opportunities. Its sporting activities extend beyond men's football to include women's football, amateur combat sports, hockey and other disciplines. The club emphasises technical development, teamwork, discipline, sporting integrity and community participation. Its operations include coaching, scouting, player recruitment, performance analysis, administration, commercial partnerships, communications, ticketing and supporter engagement. Casa Pia AC also promotes solidarity and social responsibility, reflecting its historic association with an institution established to support children and young people. The club works with sponsors, local organisations and sporting partners to develop its teams and broaden its community presence. In recent years, Casa Pia has continued to strengthen its professional football structure while preserving its traditional identity and investing in player development. Its long history, connection with Lisbon and return to the highest level of Portuguese football make it a notable part of the country's sporting landscape.