Biofilm formation is a preferred mode of growth for bacteria and an intricately complex developmental process. Biofilms on hard and soft tissues in the oral cavity are critical for determining the balance between oral health and disease. Many studies have demonstrated the presence of heterogeneous niches formed during biofilm development, leading to significant variation in gene expression across the biofilm architecture. Although much of this heterogeneity can be attributed to microenvironmental differences formed within the biofilm, recent studies have revealed that some aspects of biofilm heterogeneity arise as a result of the stochastic expression of genes and/or cellular processes. This previously unrecognized diversification is predicted to benefit the population through the division of labor and as a “bet hedging” strategy that better prepares for unpredictable changes in environmental conditions. In this chapter, we explore how biofilm heterogeneity is due to both environmental influences and genetic factors and explore the predicted benefits it may serve for the biofilm community.