The basic band consisted of Dwight Twilley (guitar, piano, lead and harmony vocals), Phil Seymour (drums, bass, percussion, lead and harmony vocals on the Dwight Twilley Band songs), and Bill Pitcock IV (lead guitar); other musicians include Leon Russell, Tom Petty and Susan Cowsill.

Most of the production is credited to Twilley and Seymour, although some other producers who worked on songs on the record include Jack Nitzsche, Leon Russell, Robin Cable and Chuck Plotkin.

Of the rest, two of the songs are the original mixes of the first Twilley Band single ("I'm On Fire" b/w "Did You-C-What Happened?

Some of the other Cable-produced numbers ended up as bonus tracks on the CD issue of Sincerely.

All in all, only two Cable-produced numbers are believed to have never been released: versions of Sky Blue and Shark (In The Dark), which appear on this collection in alternate recordings.