I’ve found that each time I lean in, it gets a little easier to quiet the voice of insecurity and fear, as I focus on making my future a wild success.

Two weeks. That was how long I worked on an email to Joanna Barsh, the most powerful woman at McKinsey & Company. To say that I admired her is an understatement; I was borderline obsessed with her work.

When I first applied, I didn't think I was good enough to get a job at McKinsey. After all, I was a sociology major, not a business major. I carried that thought — of not being smart or talented enough — with me as I interviewed and even as I accepted the job. On my first day of work, I looked around my co-workers and felt inferior. Surely they would realize I had tricked them into hiring me, and just as quickly as I had landed, I would be sent packing.

Before I joined McKinsey, I already knew that Joanna Barsh was someone I wanted to work with. Her interests paralleled the research I had done in school, so I knew my background would be a great fit for the women in leadership project she was leading at the firm. Still, my desire was in direct conflict with my fear that I wasn’t smart enough.

I must have drafted my email to Joanna a million times (and put off sending it another million). My request was simple: to have some involvement in her leadership program. I was worried she wouldn’t respond, or worse, she would reply and let me know my biggest fear was true, that I wasn't good enough. Finally, after several drafts, I took the plunge and hit send.

Joanna responded within five minutes. I still remember shaking with excitement as I replied to her with my availability.

Sending that email changed everything. Leaning in gave me the opportunity to work for my role model, who became not only a mentor but also a sponsor. Her support on a personal level as well as within the consulting firm ultimately shaped my future and helped me to develop the self confidence I needed to become an entrepreneur. Today I run my own company, which focuses on the leadership development of Gen Y women. Over time, I’ve found that each time I lean in, it gets a little easier to quiet the voice of insecurity and fear, as I focus on making my future a wild success.