(Reuters) -- Sprint Nextel, the No. 3 U.S. mobile service, is merging sales and marketing for its business and consumer operations as part of a streamlining that includes the departures of four top executives, according to Sprint CEO Dan Hesse.

The move aims at more efficiency in a rapidly evolving wireless market in which many customers buy services as individuals but utilize services tied to employer-related contractual discounts.

As the wireless market has evolved, the lines between consumers and businesses have blurred, Hesse said in a memo to employees sent Friday morning and obtained by Reuters.

We believe that we no longer need to support two separate business units (consumer and business), and that it is more logical now to evolve to unified marketing and sales organizations, Hesse said in the memo. Because of the enormous investments we're making this year in Network Vision and in the iPhone, we need to consistently be looking for ways to be more efficient.

Hesse said all consumer and business sales functions will be overseen by Paget Alves, chief sales officer, and all consumer and business marketing functions will be led by Bill Malloy, chief marketing officer. M2M (machine to machine) will transition to Matt Carter, the president of Wholesale and Emerging Solutions.

Bob H. Johnson, president-Consumer Services Group; Danny Bowman, president-Integrated Solutions; John Carney, senior vice president-Consumer Marketing; and Chris Rogers, senior vice president-Corporate Development & Spectrum, are leaving the company, Hesse said.

(Reporting by Carey Gillam; Editing by Bernard Orr)

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