Today we mourn the passing of a giant.

William H. Gates Sr. was a great man whose warmth and humanity could fill any room, whose generous spirit lifted others to be their best and whose kindness will be felt for generations.

We met Bill Sr. and his wife Mary early in our tenures at Microsoft, and in addition to becoming dear friends and neighbors, they instilled in us the imperative of giving back to community. For those of us who were lucky enough to work alongside Bill Sr., his presence was a daily inspiration and a bulwark against cynicism. He found joy in being in service to something bigger than himself, and at a time in his life when most people would have logged decades in retirement, his presence each day in the halls of the Bill & Melinda Gates Foundation was a reminder to all of us that there is no greater calling in life than to serve others.

Bill Sr. knew how to connect with people from all walks of life—from global leaders to families experiencing homelessness to the young people who had the opportunity to go to college because of the scholarship funds he championed. He made each of them feel seen and heard and valued. He traveled the globe as an advocate, but would also roll up his sleeves to clean a homeless shelter in Seattle. He inspired a generation of philanthropists—especially Bill and Melinda, his beloved son and daughter-in-law.

Our hearts go out to the Gates family and all who knew and loved Bill Sr.