and Linda Turner. Porter and Turner were eventually replaced by Janet Harmon and Helen Scott and then subsequently by Sheila Ferguson and Valerie Holiday. The line-up from 1967 to 1976 was Pinkney, Valerie Holiday and Sheila Ferguson, who would go on to sing lead on most of the group's biggest hits. This line-up topped the US Hot 100 as featured vocalists on the MFSB single "TSOP (The Sound of Philadelphia)" in 1974, and had seven UK Top 40 hits, including the 1974 single "When Will I See You Again", which was a huge international hit, reaching the Top 5 in seven countries, including number two in the US and topping the UK Singles Chart. When Pinkney left the group in 1976, she was replaced by a returning Helen Scott. This line-up had four UK Top 20 hits, including "Woman in Love", which reached number three in 1979. Ferguson left for a solo career in 1986.

     The group's most stable line-up was from 1989 to 2010, with Cynthia Garrison joining Holiday and Scott. They achieved a final UK chart entry, reaching number 54 in 1998 with a dance cover of "Last Christmas". Garrison left the band at the end of 2010 due to health reasons, and was replaced by Freddie Poole in 2011. The group's 2016 album, Strategy: Our Tribute to Philadelphia, was their first studio album release with Poole as a member. Valerie Holiday is the longest serving Degree with almost 56 years of continuous service to her name. Helen Scott remains the only member who was active during the Swan Records era.