Anderson was named an All-American in his senior season and set a school record with 14 career interceptions. He was drafted by the Dolphins in the 1968 AFL Draft in which he was named the league defensive rookie of the year. He was a three-time Pro Bowler in 1972, 1973 in which he was NFL Defensive Player of the Year and in 1974 in which he was one of the leaders of the Dolphins well known No Name Defense. Anderson was also the president of the National Football League Players Association from 1975 until he retired.
In his 9 AFL/NFL seasons, Anderson recorded 34 interceptions, which he returned for 792 yards and 3 touchdowns. He also recovered 15 fumbles, returning them for 100 yards and a touchdown. On special teams, he gained 430 yards returning kickoffs and punted the ball 9 times for 335 yards.
After retirement, Anderson became a successful businessman and a Florida state senator. In 1993, he was enshrined in the College Football Hall of Fame. His brother is Bobby Anderson, who was a running back for Colorado. His son, Blake Anderson played wide receiver for the University of Colorado.
On December 3, 2006, Anderson was inducted into the Miami Dolphin's Honor Roll during halftime of the Dolphins-Jaguars game. He is one of two players being inducted this year, the other being Richmond Webb, who was inducted December 25 against the Jets. Anderson will be the first individual defensive back inducted into the Honor Roll. The entire 1972 Miami Dolphins roster is a part of the Honor Roll, including Anderson.
On December 3, 1973, Anderson had perhaps his greatest personal effort in his career, becoming the 7th player to intercept 4 passes in a single game in NFL history in the Dolphins 36-20 victory over the Pittsburgh Steelers. Since that date, another six players have tied that mark.