From Third World to First: The Singapore Story 1965–2000 by Lee Kuan Yew — The founding prime minister's account of how he built the country. Blunt, unsentimental, and revealing. Whatever you think of him, this is indispensable for understanding why Singapore is the way it is.
Notes from an Even Smaller Island by Neil Humphreys — A British journalist's account of moving to Singapore and living in a public housing block in the early 2000s. Self-deprecating and genuinely funny, it captures daily life in a way no official guide does. Good on hawker centres and the oddities of Singlish.
The Great Reclamation by Rachel Heng — A sweeping historical novel following a fisherman's family from the 1940s through Singapore's transformation into a modern state. One of the best recent novels about the country, and the land reclamation theme is particularly apt.
How We Disappeared by Jing-Jing Lee — A historical novel about the Japanese occupation of Singapore and a young woman taken as a comfort woman. Difficult but important; it covers a period of Singapore's history that is often skimmed over.
Crazy Rich Asians by Kevin Kwan — Frothy and entertaining, the novel is essentially a tour of Singapore's wealthiest social circles. Not deep, but it is specific about places and the texture of a certain Singapore life. Read it on the plane.
Saint Jack by Paul Theroux — A short novel set in 1970s Singapore, following an American pimp and fixer who knows the city's underside. The Singapore Theroux describes has largely disappeared but the book is vivid and funny.
The Singapore Grip by J.G. Farrell — A novel set in the months before the Japanese invasion of 1942, centered on a British colonial trading family. Farrell is excellent on the complacency and delusion of the colonial class as Singapore fell.