The Eastern Daily Press reported on 21st August 2000 that American international left-back Gregg Berhalter would join Norwich for a week's trial. Aged 27, this New Jersey born defender was then with Cambuur Leeuwarden, the Dutch side from which Norwich signed Raynond De Waard.

Progressing throuhg the USA's Under-20 and Under-23 sides, he made his international debut in 1995 playing in the Copa America in Uruguay. However the next two years saw him break his right foot three times, break his left ankle and tear his ligaments. He returned from injury to play in the Confederations Cup in Mexico in 1999. He started his European career with Fc Zwolle of the Dutch Second Division before transferring to Sparta Rotterdam in 1996 and to Cambuur in the summer of 1997, from where he was available on a free transfer in 2000.

Impressing in the 4-1 Reserve Team victory over Bristol City with a goal, Norwich offered a contract to Greg only for him and his agent to reject it in favour of a trial at Bolton Wanderers. As well as Norwich, Huddersfield had offered him a trial and then a contract only for it to be rejected by his agent. Bolton were also gazumped as Premiership side Everton showed an interest. None of these transfers materialised and Gregg was next seen at Selhurst Park trialling with Crystal Palace's reserves in February 2001. Available on a free transfer, Gregg signed for the Eagles and was on the bench for Palace in their ill-tempered 1-1 draw with Norwich on 17th February 2001.

Gregg played for the USA in their victorious Gold Cup campaign in 2002 but feard for his World Cup place as he was not a regular in Trevor Francis' Palace side. On his return from the states, he requested to go on the transfer list in order to gain first team football prior to the World Cup. Despite turning out for Palace's reserves, Gregg was selected for the US World Cup squad and made 2 appearances in the finals. However Palace boss Trevor Francis wouldn't change his mind and Gregg departed for Greece on 9th July 2002 for discussions with Iraklis with whom Palace had agreed a fee. This Greek move fell through but on August 29th 2002, Gregg finally left Palace, joining German Bundesliga side Energie Cottbus on a free transfer. He signed an extension until 2006 at the end of his first season in Germany. In August 2006, he transferred to 1860 Munich where he was captain. In 73 appearances, he scored eight goals.

In April 2009, Gregg returned to the USA to sign for the LA Galaxy. They won the MLS title in 2011 and the Western Conference title in 2009 and 2011.

Following a season as Los Angeles Galaxy's player / assistant manager, he retired and was signed as the new manager for Swedish club Hammarby IF on 12th December 2011. He was dismissed on 24th July 2013 for a lack of offense.

He became Sporting Director of MLS side Columbus Crew on 16th November 2013.They reached the MLS play-offs four times and the MLS final in 2015 with Kei Kamara scoring Columbus’ goal in a 2-1 defeat to Portland Timbers.   

On December 2 2018 he was appointed as manager of the United States national team, succeeding Dave Sarachan. He won his first international victory the following month against Panama. He originally served in the role from 2018 to 2022. They won the CONCACAF Gold Cup in 2021 and the CONCACAF Nations League in 2019/20. Following the expiration of his contract, US Soccer employed a number of interim managers until Berhalter returned on 16th June 2023. He left after the team's early elimination in the 2024 Copa America group stage.

On 8th October 2024 he was appointed as Head Coach and Director of Football for the Chicago Fire. He later employed Gregg Broughton as Sporting Director.

Berhalter's son Sebastian is a professional footballer playing for the Vancouver Whitecaps.