Monitoring quality traits is very important for the tomato industry at different stages of the production cycle including agricultural production, harvesting, and processing. The most important tomato quality traits include color, consistency, sugars, and acids, in addition to other components that are important contributors to the flavor of the product. Consumer acceptance and behaviour when buying tomato products are influenced by nutritional value, sensory characteristics (flavor, color, aroma), consistency, acidity, and serum separation, which correspond to quality parameters that are commonly monitored in tomato production. Cutting-edge sensor technologies can provide a valuable window into in-process food manufacturing to permit optimization of production rate and quality of tomato products. The new generation of optical systems incorporate the analytical precision for chemical identification and quantitation with a spectral resolution equivalent to that of benchtop instruments. In this chapter the current state of technologies that provide rapid assessment of tomato quality is presented. Advances in microelectro-mechanical systems (MEMS), semiconductors, lasers, computing capabilities, and chemometrics have allowed the miniaturization of systems for field and online applications. Technologies such as spectrophotometers, colorimeters, hyperspectral imaging, and vibrational spectroscopy (NIR, mid-IR, and Raman) have benefited from these innovations with commercial micro- and nanoscale devices that have found applications in quality assurance. Technologies that reveal early quality problems can provide a competitive edge to the industry by providing real-time information, thus preventing consequences of increased costs (recall, liability, withdrawals), lost revenue or market share, and damaged brand.