Poly(3-hydroxybutanoate) (PHB) is a biodegradable polyester, conventionally processable due to its thermoplasticity. Even though PHB has many advantages over other plastics, its wide use is hindered by unacceptable brittleness, high price and a high sensitivity to thermal degradation. The present paper provides an overview of basic properties of PHB and of possible ways of their modification, which could lead to a material with improved properties, suitable for application on a larger scale.