How does one woman manage the chief finance role at two separate but related companies? With good, old-fashioned preparation — and lots of communication.

That’s Mary Sullivan’s answer. Sullivan is CFO, executive vice president and treasurer of Susser Holdings Corporation, the Fortune 500 operator of convenience stores, including the Stripes chain. Susser also owns the general partnership  fuel distributor Susser Petroleum Partners, where Sullivan also leads finance. In her combined role, she regularly “prepares for the downside,” she said in an interview with CFO at CFO Publishing’s Women in Finance awards luncheon and working session in May.

But at the finance helm of two firms simultaneously, that “downside” can mean anything from unknown fuel margins to a new brand of taco not selling well enough in a particular region.

So how does she handle the dual roles? “In today’s economy, things are changing so quickly that you’ve got to be prepared for what might happen.” Instituting risk management policies and procedures, she says, is a big part of her daily tasks at both business units, particularly with food and supply cost pressures. “It’s so much more important today.”   

That kind of advance planning can also come in handy amid unpredictable fuel prices. “Retail fuel margins are going to be volatile. There’s really not a lot we can do about it. We can influence them slightly but we really can’t control them,” she says.  

To cope with fuel margins that are “going to be one of the key unknowns quarter to quarter,” she uses internal metrics to project more normalized fuel margins over time.

Susser Petroleum Partners, which is the largest non-refining motor fuel distributor in Texas, brings over 1.4 billion gallons of motor fuel annually to its Stripes convenience stores. It is also in the process of adding new third-party fuel dealers, new unbranded convenience stores and more commercial customers to its fuel distribution business as well as pursuing acquisitions of other wholesalers.

Its retail operations, though not quite as volatile, can be just as trying. “That is challenging being a convenience store operator that’s public,” she adds.  Susser Holdings operates retail stores in Texas, Oklahoma and New Mexico. With few exceptions, most of the convenience stores feature food from the Laredo Taco Company, its proprietary restaurant business.

Sullivan didn’t start out wanting to keep an eye on the finances of a retail company at the same time as a fuel distributor, but things just ended up that way.

Sullivan joined Susser in 2000 as the vice president of finance after serving most recently as the director of finance for the City of Corpus Christi and previously as the controller at specialty product maker Elementis Chromium and as treasurer at the Central Power and Light Company. Sullivan was promoted to CFO of Susser Holdings in 2005.

Susser Petroleum went public last September, which provided even more responsibilities for Sullivan, though she was certainly busy enough when it was private. Susser Holdings went public in 2006.  

It also helped having a well-rounded finance background and never losing site of the “big picture,” according to Sullivan. Having worked in accounting, internal audit, budgeting and treasury throughout her career, Sullivan admits she “got to do a lot of the fun things.” 

Now, Sullivan handles the head finance role for both business units, which means dealing with two boards of directors and two sets of financial reports. But she credits her staff with getting all of the financial statements out on time. “I have a great staff. They really stepped up to the challenge.”

She plans on “streamlining” the process of her firm’s financial reporting even further over the next six months. “It’s really going to make us better.”

While juggling those tasks might be enough to push any CFO to the brink, Sullivan says constant communication with staff, analysts and investors help to smooth out some of the wrinkles that can occur along the way.