National Small Business Week kicked-off in San Francisco at Twitter’s headquarters Monday. Political and business leaders from across the country, including House Minority Leader Nancy Pelosi, U.S. Small Business Administration head Maria Contreras-Sweet and San Francisco Mayor Ed Lee all spoke about the importance of small businesses to the national economy. “I think there is nothing more optimistic anybody can do than start a small business,” said Pelosi. “Small businesses are the engines that drive California’s economic growth, and the Bay Area is a hotbed of entrepreneurship in America, leading the way for small businesses across the country.” The 10th annual celebration of Small Business Week in San Francisco launched Monday night at Square headquarters and continued with the 4th annual Small Business Conference which featured new TED-style talks and panel discussions that were streamed live online. Additional activities will be taking place throughout the rest of the week, including U.S. Small Business Administration workshops, a Latino entrepreneurs panel discussion, and neighborhood sidewalk sales. The Chamber co-chairs Small Business Week and co-founded the initiative 10 years ago. Read more.