Plants enjoy their entire life exactly where they were initially rooted. Because of this fixed life pattern, plants have to devise a different type of strategy than animals to survive the numerous biotic and abiotic challenges. Many different plant hormones that act alone or in concert underpin these mechanisms. Brassinosteroids (BRs) collectively refer to plant-originated $5alpha-cholestane$ steroids that elicit growth stimulation in nano-or micromolar concentrations. BRs that are biosynthesized using sterols as precursors are structurally similar to the cholesterol derived, mammalian steroid hormones, insect molting hormones and ecdysteroids. BRs have been known for decades to be effective in plant growth promotion. However, definitive evidence for their roles in growth and development remained unclear until the recent characterization of BR dwarf mutants isolated from Arabidopsis and other plants. This review aims to provide a cohesive summary of information obtained from the molecular genetic characterization of mutants that are defective in sterol and BR biosynthetic pathways.