Advancements in wireless technologies have made it possible to build wireless enterprise applications. An enterprise application calls for challenging requirements such as two-way data transfer, complex business logic, and multiple system users. These applications will make great impact to the operations of a company that will result in the increase of the company’s revenue.This chapter examines and develops one enterprise scenario, a customer support system, using Java 2 Micro Edition (J2ME). J2ME allows applications to be executed locally using a mobile device’s processing capacity and resources. We outline the design of a relational database to store frequently accessed data and describe the usage of XML for data exchange for better interoperability with back-end systems. Extensions to mobile commerce (m-commerce) are also considered. Bank account information and financial transaction instructions are treated as data to be sent over the wireless network. However, as in the case of e-commerce, the security of the transaction is the primary concern and some cryptography techniques need to be used.