Castillo's tenure was marked by an emphasis on infrastructure investments, notably road building and rural electrification. Two landmark projects include the Cuesta de El Portezuelo road and the San Francisco Pass, which improved links between both sides of the rugged Ancasti range, and facilitated commerce with neighboring Chile, respectively. The governor responded to the province's judicial bottlenecks by decreeing that, counter to the provincial constitution, candidates from anywhere in Argentina could be eligible for the bench in Catamarca. Castillo was challenged in his 1995 campaign for reelection by Ramón Saadi, who was defeated by 8%; the strength of the UCR in Catamarca led Castillo to forego joining the Alliance formed at the national level with the center-left Frepaso in 1997.