Molecular imprinted polymers (MIPs) are molecular recognition elements that can be tailored towards a wide variety of target molecules. These human-made materials are relatively easy to prepare and have found a broad application as substitutes of antibodies or enzymes. They have been successfully applied to the development of chromatographic or solid phase extraction methods and have attracted a great interest for the development of electrochemical, piezoelectrical or optical sensors. In parallel with the classification of biosensors, MIP-based devices can work according to two different detection schemes: affinity sensors (“plastic-bodies”) and catalytic sensors (“plastic-enzymes”). These devices can be interrogated using different optical techniques, such as fluorescence, light absorption (UV-Vis, Infrared) spectroscopy, chemiluminescence, surface plasmon resonance, or Raman scattering. This paper reviews the main developments and applications of MIPs in the area of optical sensors with special emphasis on their analytical applications.