MarkWest Energy Partners, LP (MWE)

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        In this report, unless the context requires otherwise, references to "we," "us," "our," "MarkWest Energy Partners" or "the Partnership" are intended to mean MarkWest Energy Partners, L.P. and its consolidated subsidiaries; references to "the Corporation" or "MarkWest Hydrocarbon" mean MarkWest Hydrocarbon, Inc.; references to the "General Partner" mean MarkWest Energy GP, L.L.C., the general partner of the Partnership; references to the "Board of Directors" or the "Board" mean the Board of Directors of our General Partner; and references to the "Limited Partnership Agreement" or "Partnership Agreement" refer to our Third Amended and Restated Agreement of Limited Partnership effective as of February 21, 2008.

        This proxy statement contains information related to the 2008 Annual Meeting of our Common Unitholders, to be held on June 4, 2008, beginning at 10:00 a.m., Mountain Daylight Time, at our headquarters, 1515 Arapahoe Street, Tower 2, Suite 700, Denver, Colorado 80202-2126, and at any postponements or adjournments thereof.

ABOUT THE MEETING

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        Throughout this document we make statements that are classified as "forward-looking." Please refer to the "Forward-Looking Statements" included later in this section for an explanation of these types of assertions. Also, in this document, unless the context requires otherwise, references to "we," "us," "our," "MarkWest Energy" or the "Partnership" are intended to mean MarkWest Energy Partners, L.P., and its consolidated subsidiaries.

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