Answer
Sommer won the Swiss Super League four times with Basel. He was part of the Basel team that won the league in the 2010-11, 2011-12, 2012-13, and 2013-14 seasons. Sommer was a key player for Basel during this period, making over 200 appearances for the club. He was also part of the Basel team that won the Swiss Cup in 2012 and 2013.