Rui Osório de Castro was born in Oporto in 1950. At the age of two, he moved to Mozambique where he remained for 9 years until he joined the Military College of Lisbon in 1961. He returned to Mozambique and in 1974 graduated in civil engineering at the University of Lourenço Marques.

He started his professional activity in the Railways and Transportation of Mozambique and shortly thereafter became Director of Special Artworks at Construções Azevedo Campos.

In late 1975 and still in Mozambique, marries Maria Karla Bragança Belard Rebelo. Their two sons, Philip and Catherine, were born in Lisbon.

After returning to Portugal in 1977, he became a member of Soares da Costa Construction Company, as Head of Division of Construction, Director of the Algarve Delegation and Vice-President of the General Management of the same company, headquartered in Porto. In 1989 he joined Engil, as an Executive Director of the Board of Directors. A year later, he became Chairman of the Board of Directors of Sociedade de Construções H. Hagen, a company that he later acquired.

His unexpected death in 2006 did not allow him to fulfil the dreams and the many projects he had in mind.