Maksim Aleksandrovich Chmerkovskiy (born January 17, 1980) is a Ukrainian-American Latin–ballroom dance champion, choreographer, and instructor. He is widely known as one of the professional dancers on the American television series Dancing with the Stars, on which he first appeared in season two. In his 17 seasons as a competing pro on the show, Chmerkovskiy made it to the final round five times, with two runner-up and two third-place finishes. On May 20, 2014, Chmerkovskiy, paired with Olympic ice dancer Meryl Davis, won his first Dancing with the Stars title. Chmerkovskiy has also starred in the Broadway productions of dance shows Burn the Floor and Forever Tango.

Maksim Aleksandrovich Chmerkovskiy was born on January 17, 1980, in the Ukrainian port city of Odessa. At the time, Ukraine, known by the Ukrainian Soviet Socialist Republic, was a constituent republic of the Soviet Union. His mother, Larisa Chmerkovskaya, is Christian, and his father, Aleksandr "Sasha" Chmerkovskiy, is Jewish; Chmerkovskiy has described himself as Jewish. He has a younger brother, Valentin Chmerkovskiy (born 1986), who is also a professional dancer.

Chmerkovskiy began dancing at the age of four when his parents enrolled him in a school of aesthetic education. The aim of the school was to train children to become young gentlemen or ladies, and the education included manners and ballroom dance. He eventually began competing in ten-dance, which includes both ballroom and Latin dances. As a child, Chmerkovskiy also participated in tennis, soccer, and swimming.

At age 13, he broke his right leg in a skiing accident and had a titanium rod put in to stabilize his leg. Doctors foresaw long-term difficulties and little possibility of a dancing career; however, he recovered and was dancing again six months later.

The family immigrated to Brooklyn, New York, in 1994. The challenges of immigration for Chmerkovskiy and his family included financial and language barriers. On his second day in the United States, Chmerkovskiy had a new pair of roller blades stolen. Moving to the United States also gave Chmerkovskiy the opportunity to rededicate himself to dance. At 15 he began working at a local Russian restaurant, dancing as entertainment. Working at the restaurant, Chmerkovskiy decided winning competitions as a dancer would be a way to argue for higher pay.

As a dancer, Chmerkovskiy competed at the professional level in the International Latin category. With partner Elena Grinenko, with whom Chmerkovskiy competed from 2002 to 2005, Chmerkovskiy achieved the rank of 2nd in the United States and 7th in the world among professional international Latin couples.

At age 16, Chmerkovskiy and his father opened a youth-oriented competitive dance studio, Rising Stars Dance Academy, on the second floor of a building his father owned in Ridgewood, New Jersey. Chmerkovskiy said he chose New Jersey because there was a plethora of dance studios that he disliked already established in Brooklyn. The studio relocated a few times until it ended up in Saddle Brook, New Jersey. He said in 2011 of choosing a New Jersey location, "I didn't want to open a studio that would become just one of the studios in the area. I wanted to open my studio somewhere where there was nothing like it and where people would look at it with no preconceived notions."

In 2001, Chmerkovskiy had his first major success as an instructor when he helped his brother, Valentin, then 16, and Diana Olonetskaya, 15—became the first U.S. dance pair to win a world junior championship. Chmerkovskiy also taught dancers Serge Onik and Kiki Nyemchek, both of whom competed on So You Think You Can Dance, finishing in the top fourteen in season 11 and fourth in season 14, respectively.