In this talk I will provide several examples of photochemical reactions we used, or developed, to access a variety of structurally novel saturated heterocycles. Specifically, I will discuss our studies in the area of pyrrolinium photochemistry, the development of a Norrish-Yang reaction variant for accessing azetidines, and the photochemical decarbonylation of small heterocycles which give ylides (which react with pi systems). Two vignettes are also included: one is about an alternative to photochemistry to access spirocyclic pyrrolidines (nickel catalysis), and the other is about using the compounds we made and our findings upon exposing living cells to them. The discussion will feature quantitative measurements and models that aided and guided our development of described methods.