Isabel Allende's 1984 novel Of Love and Shadows doesn't have a concrete setting. However, there are several factors that can be taken into consideration when determining where the novel takes place.
Of Love and Shadows tells the tragic love story of Irene Beltrán, a reporter and magazine editor, and Francisco Leal, a talented photographer, who live and work in an unnamed country governed by an authoritarian military dictatorship. The circumstances and the environment in the novel are very similar to the environment of Chile during the Pinochet dictatorship, which is why many agree that the novel takes place in Chile and represents all the brave journalists who weren't afraid to stand up against the dictatorship. The fact that most journalists, including Irene and Francisco, had to take a stand in secret to avoid torture, exile, or even death only further strengthens the assumption that the novel is set in Chile.
When writing Of Love and Shadows, Isabel Allende actually took inspiration from the various journalistic texts that she's collected over the years working as a journalist, both in Chile and later on in Venezuela. She was involved in Chilean politics and was active in helping victims of the cruel, brutal, and inhumane Chilean political system, but after realizing that it was no longer safe to stay in Chile, she and her family fled to Venezuela. Thus, it can be reasonably inferred that the novel takes place in Chile; a specific city or town, however, is never mentioned.