Peter Caulfield picked up the inaugural Manager of the Year award in 2009, sponsored by the Scottish Sun newspaper, when he lifted the prize at the first ever Scottish Women's Football awards night at Hampden Park.
Following spells coaching in boys football and the men's amateur game, he accepted an offer from Monklands Ladies to become Manager and guided them in his first season to the 1997/98 Scottish 1st Division West title, with a 100% win record, and into the Scottish Women's Premier League for the first time. After a single year in charge in the Premier League, where he consolidated their position, he left after an approach from Glasgow City, who themselves had just been promoted to the Premier League, stating he felt Monklands Ladies were unable to match his ambitions.
Caulfield was appointed manager of Glasgow City after they won the 1998–99 Scottish Women's 1st Division West title, in their inaugural year in women's football, and remained in charge until his departure in December 2010.
Amazingly the team also won the Scottish Women's Football League Cup, in November 2008, which comprised teams from all three regional second divisions, together with the 12 Scottish Women's First Division clubs. When the team lifted the trophy, beating Celtic's reserve side 3–0, in the final at Lesser Hampden, they became the youngest team to lift the trophy as well as the only Second Division club to do so.
Caulfield joined Celtic in February 2011 following his surprise departure from Glasgow City where he spent 11 years in charge, winning five Scottish Women's Premier League titles, three Scottish Cups and two Premier League cups. He was appointed manager at Celtic in January 2013 following two years spent as assistant manager to Robert Docherty.
He resigned from Celtic on 25 July 2013, only five months into his first season in charge of the team. In a statement, the club cited "work and family reasons." for his departure.
In September 2016, Caulfield rejoined Celtic once again as Assistant Manager.