Constraints play an important role in conceptual modeling. In general, the specification of constraints, both static and transition, must be done in some logic-based language. Unfortunately, the resulting formulas may be complex, error-prone and difficultto read. This explain why almost all conceptual modeling languages have developed aspecial, easy-to-use syntax (language features) to state the most common constraints. Most features (often with graphical symbols) developed so far are concerned with staticc onstraints (like keys, partitions or cardinalities), and very little work has been done for transition constraints.In this paper, we identify six temporal features, three related to class populations and three to attributes. The corresponding transition integrity constraints appear in almost any conceptual model and their specification is necessary and important. We believe that ourtemporal features make their specification simple and practical. We have named each feature, and provide a declarative and procedural formalization for them.