IP Multimedia Subsystem which is standardized by 3GPP is an important step to improve the delivery of innovating IPTelephony and Multimedia services to the customers in 3G and B3G networks. However, IMS is almost access independent and multiple access technologies such as UMTS, WiFi, WiMax, xDSL and Cable Technology can benefit from IMS services. In 3GPP Releases 6, an architecture for access to 3G services (including IMS services) from WLAN technologies has been standardised and the work is being completed in next releases. The goal of this architecture is to allow the 3G customers to be roamed in WLAN and access to their services in 3G domain. To this end, 3GPP has chosen a Master/Slave approach which does not bring forth IMS services directly for WLAN customers and limit the applicability to some limited scenarios such as when the WLAN and 3G domain are under control of a same operator. In this paper we propose different scenarios for adopting/adapting IMS in/for WiFi as the dominant WLAN technologies. These scenarios allow the independent WiFi operators to provide advance IP Telephony services based on IMS by themselves in addition to the broadband Internet access. These scenarios are proposed with considering the capability of various WiFi operators.