FORTUNE Most Powerful Women Summit - Day 2

During Fortune's Most Powerful Women Summit on Wednesday, Mary Barra, General Motors' executive vice president of global product development and global purchasing and supply chain - and in the running to be GM's next CEO - says she gives her employees one directive: "No more crappy cars."

"[Employees] want to go and do their best. I feel so much of what I need to do is set up the systems, enable the processes and have the right leadership," Barra says. Empowering employees and expecting their best work is a concept that isn't so strange to relatively new tech companies such as Google or Facebook, but for GM to do the same, Barra worked at "getting rid of that bureacracy that can creep into a company that's a hundred years old," she says.

While she worked as vice president of human resources before her current position, she fought GM's bureacracy by taking the focus of HR employees off reports and paperwork and reducing the company's policy manual by 80 percent, which included cutting a 10-page dress-code section. Her reasoning for getting rid of the dress code and replacing it with an easily remembered "dress appropriately" is simple: if employees are managing teams of people and million-dollar budgets, GM doesn't need to tell them how to dress, she says.

Of course, Barra was asked if she could name a crappy car from GM's past, but she didn't bite. Watch the interview in the video below for 15 minutes of insight into GM's culture.