Many countries have introduced, or are planning to introduce in the near future, performance/objective-based codes. In a performance/objective-based code, the level of safety provided to the occupants in a building by a particular fire safety design will be assessed by the use of engineering analysis of fire development and occupant evacuation. Central to this performance-based approach is the use of suitable design fires that can characterize typical fire growth in a fire compartment. This paper gives a description of what features of design fires are needed and how they can help analyze fire hazards to the occupants in a building as a result of smoke movement, untenable condition in the stairs, and occupant response and evacuation.