Interleave Division Multiple Access (IDMA) is one of the competitors for next generation wireless systems .IDMA not only inherits all the advantages of CDMA but also has the capability to overcome its deficiencies.This paper outlines a survey on interleave-division multiple-access (IDMA) technique which exploits the interleaving as only means of user separation instead of by different signatures as in a conventional code-division multiple-access (CDMA) scheme. IDMA scheme can achieve near single user performance in situations with very large numbers of users while maintaining very low receiver complexity. This technique inherits many advantages from CDMA, such as diversity against fading and mitigation of the worst-case user interference problem. The parallel and simultaneous execution of repetitive functions can be used to overcome the significant time delays involved in previous simulations of IDMA system. This paper presents an overview of IDMA and discusses the main features and areas of application as the future air interface access schemes for IMT-2000/UMTS.