Jacopo Vignola's design for Il Gesu in Rome is important for several reasons. As a result of the Council of Trent, a new kind of architecture was established in Rome. Il Gesu, as the Jesuits inaugural church, reflected their mendicant status with reliance on donations and focus on education and missionaries, it also established the shift toward desegragating congregations. With the abbreviation of side aisles and transepts, a larger nave was allowed. Instead of large aisles, carved out chapels were created. It also eased the problem of joining the exterior levels. There are Albertianesque scrolls to suggest continuity. Following patron Cardinal Farnese's wish that all would have access to the altar, Vignola combined a suppressed basilica plan with a Latin cross plan. Additionally, Farnese was interested in the sound quality. In order to project the preaching for all to hear, a barrel vaulted nave was decided upon.
Vignola was relieved of his position on Il Gesu, the creator of this facade is Giacomo della Porta (1537-1602). He followed, to some degree, Vignola's original plan. There is a double tabernacle facade, with horizontal and vertical symmetry. Framed by a pediment, the top story seems to be set back from the more plastic lower story. The emphasis is on the portal, where there are double pilasters and columns. The exterior structure is reminiscent of Palladio's Il Redentore, with a strong sense of compact focus.
Also, the interior decoration is not as Vignola had planned. His wish was to reflect the humble mendicant order, lighter colors, whites, and the simplification utilized by Il Redentore. Instead there are lavish frescoes by Giovanni Battista Gaulli.