The objective of TERESA is to define, demonstrate and validate an engineering discipline for trust that is adapted to resource constrained embedded systems. We define trust as the degree with which security and dependability requirements are met.Resource constrained embedded systems are characterized as follows:•\tThey belong to different application sectors•\tComputing resource are mostly statically determined and allocated through a process consisting of a configuration phase and a build phase•\tThey are generally high integrity systems with strong assurance requirements. They therefore use advanced engineering disciplines.The proposed approach is to use a model-based repository of security and dependability patterns:•\tApplication sector trust models are defined as profiles (e.g. UML, SysML profiles), based on a common trust meta-model•\tSecurity and dependability patterns, platform independent are identified and defined for each application sectors (some patterns could be used by several application sectors)•\tFormal properties on security and dependability are defined and validated for patterns used in application sectors requiring this level of assurance•\tPlatform dependent implementation of the patterns are of the patterns are guided with very precise requirementsThe engineering process for resource constrained embedded systems will be validated in four application sectors: automotive systems, home control systems, industry control, and metering.