Valters first played professionally in 1998, for
ASK/Brocēni/LMT. In 2000, Valters signed his first foreign contract, with
Antalya Büyükşehir Belediyesi, but played there only one season. He then returned to the
Latvian Basketball League, signing a two-year contract with the newly created team
Skonto. In 2003, he played in the
NBA Summer League for the
Cleveland Cavaliers alongside number #1 pick in that draft
LeBron James. In the fall of that year, he returned to Europe and played for
Panionios. Valters did not stay there for long and in December 2004, he returned to play for
Skonto. From 2004 to 2006, he played for the Germany's
Basketball Bundesliga club
EWE Baskets Oldenburg. Then he went to
Italy and played for
Pallalcesto Amatori Udine. During the season in Italy he was named as Week 8 MVP of
ULEB Cup. In 2007, he signed a contract with
Scafati Basket, but never played there because he was injured and the team terminated his contract. In November 2007, Valters signed with Russian team
Triumph Lyubertsy. In the summer of 2008, he signed a contract with
Liga ACB team
Fuenlabrada and had a breakout season. The team wanted to retain Valters and offered him a three-year contract for about two million dollars, but Valters opted to sign a two-year contract with
DKV Joventut in July 2009 replacing
Ricky Rubio. In August 2010, he returned to
Baloncesto Fuenlabrada, where he had another great year by leading his underdog squad to the ACB League's play-offs. For the 2011–12 season he signed with
Unicaja Málaga, helping team to reach Euroleague's Top16. Kristaps ended season in Malaga as ACB's leading three-point shooter. Prior to 2012–13 season Valters joined German squad
Artland Dragons, but later returned to Fuenlabrada, where he finished the season. For the 2013–14 season Valters moved to Turkey, signing with
TED Ankara Kolejliler and guiding his team to
Eurocup Quarterfinals. During the season Valters delivered some very impressive outings that included 26 points and 7 assists in a road win over
Brose Baskets on January 29, 2014. Valters capped season with a 31-point and 6 assists performance, shooting 9-10 from three in a win over
Pınar Karşıyaka on 7 May 2014. On December 3, 2014 he signed with
Türk Telekom. On February 20, 2017, Valters signed with the Latvian team
Valmiera. On May 1, 2017, Valters announced that he has to retire from playing due to health problems. ==National team career==