Senior in-house lawyers aspiring to top corporate jobs need to work in business areas outside of legal, according to United Biscuits chief executive Martin Glenn (pictured).

The former head of PepsiCo in UK and Ireland made the comments at Legal Week's Corporate Counsel Forum last month.

"The challenge is that the lack of cross-functional experience counts against GCs in getting to the CEO level," he said. "I would never make someone a CEO with only experience of one function."

Glenn suggested there was more appetite among US GCs to move into leadership positions than there was among their UK counterparts. He singled out former Cadbury chief executive Todd Stitzer, who "proved his commerciality" by moving from general counsel into strategic and marketing roles.

"Seize related opportunities that can broaden your commercial impact," Glenn advised delegates at the forum. "It will make you more marketable."

Glenn added that general counsel and senior lawyers should increase their understanding of their businesses by spending time on the shop floor. 

"Don't be lost in an ivory tower," he said. "Occasionally go out with a sales rep and find out what it's like in their markets, or go to a factory and find out how they are handling legal disputes with colleagues."

Glenn cited the work of outgoing Iglo Foods general counsel Anthony Barratt, who developed a training programme on the fundamentals of competition law for the company's key salespeople.

"When you shift the presumption onto the operator needing to be aware and compliant, rather than leaving the guys in the legal function to clean up, it's really powerful," said Glenn. "Treat your colleagues like adults."

Glenn also urged GCs not to give their CEOs "what they want to hear".

"I don't want a GC to tell me things that make me comfortable. In any business a service function should be muscular and stand up for what it should do."

Addressing the subject of GCs' value to their businesses, Glenn said lawyers "cannot be an exception" and urged in-house teams to demonstrate efficiencies. He continued: "Sometimes when I go around legal offices I cringe at the sheer volume of paperwork there; I've seen really old-fashioned workflow processes, because they've been done for 25 years. Things can't be done like that."