Many flamelet models for turbulent non-premixed combustion assume that a turbulent diffusion flame behaves locally as a steady, one-dimensional, laminar, strained flame. While this assumption works well in many practical applications, it fails to take into account unsteady chemical kinetic effects that occur at low Damkohler numbers. Commonly used methods to account for unsteady effects are the RIF formulation [1] and conditional moment closure models [2]. These models are computationally expensive, as equations for detailed chemistry must be solved. A new, efficient, flamelet based model that incorporates unsteady effects is proposed. (C) 2003 The Combustion Institute. All rights reserved.