This paper investigates the impact of the introduction of seclusion on monastic architecture and on technical and engineering companies and professions in 16th-century Naples. Neapolitan engineers often experimented with new building techniques to cope with the problems posed by a city that was already overcrowded with bold mansions and imposing architectural volumes, but also to deal with the need to make seclusion compatible with the residents' comfort. Thus, prestigious monastic architecture increasingly patterned itself after the style of aristocratic buildings. Common features, clearly discernible from the outside, included "loggias", terraces and balconies with beautiful views of the sea. At least two generations of engineers specialized in this kind of architecture, and devised a number of features to meet the expectations of the noble nuns, including some gender-specific ones. The monastery of S. Maria della Provvidenza, for example, boasted an impressive hydraulic pump that could carry water to the top floors, thus sparing the lay sisters a lot of hard work and granting the nuns a more comfortable lifestyle.