Sister Karen Klimczak (October 27, 1943 – April 14, 2006), a Catholic nun in Buffalo, New York, was murdered on April 14, 2006. Sister Karen ministered to former convicts in the Bissonette House, a home for convicts on the city's East Side. It was one of those convicts, Craig M. Lynch who murdered her after she caught him stealing her cell phone.
Sister Karen was well known throughout Buffalo. She launched a campaign of leaving large cut out doves at the scenes of Buffalo homicides. These doves, stating "I leave Peace Prints" have become increasingly popular after Sister Karen's death.
During the 1970's Sr Karen was an elementary and junior high school teacher at St Stanislaus School in Chicopee, Massachusetts.