Schilder and Keizer first began working together in the band of schlager superstar Jan Smit, a fellow Volendam native. Schilder and Keizer were with Smit during 2005, when his reality show gained him renewed fame. That year he released two singles co-written by Keizer, "Boom Boom Bailando" and "Laura," which were big hits, reaching numbers nine and one, respectively, on the singles chart. In successive years, Smit enjoyed additional smash hits written in collaboration with Keizer, including the chart-topping singles "Als de Morgen Is Gekomen" and "Cupido" in 2006 and "Op Weg Naar Geluk" and "Dan Volg Je Haar Benen" in 2007.
In the meantime, Schilder and Keizer had put together an act of their own, and in 2006 released their full-length album debut, Nick & Simon. Featuring a series of hit singles ("Steeds Weer," "Verloren," "Vaarwel Verleden," "Herwinnen"), the eponymous album debuted in the Top Ten of the Dutch albums chart. Impressively, it charted for over two years. Its longevity was spurred on by the even greater popularity of Nick & Simon's follow-up album, 2007's Vandaag, which reached number one and spawned another series of hit singles: the chart-toppers "Pak Maar M'n Hand" and "Hoe Lang?," plus the Top Five hits "Kijk Omhoog" and "Rosanne." Vandaag eventually reached quadruple-platinum status in the Netherlands.
Third album Luister from 2009 was no less successful than its predecessor, topping the albums chart and spawning another round of number one smash hits ("Vallende Sterren," "De Dag Dat Alles Beter Is"). Fier, released one year later, sent the single "Een Nieuwe Dag" to number one as well. Both Schilder and Keizer began an association with The Voice of Holland, serving as coaches for each of the first three seasons. The duo's next two albums both peaked at number one, Symphonica in Rosso in 2011 and Sterker in 2012. The former was led by the number one single "Wijzer (Dan Je Was)," while the latter produced one of their biggest career hits, "Julia." (In a dream marketing move, no less than 150 versions of the song were released, each with different female names substituted.) The holiday-themed Christmas with Nick & Simon: Merry X-mas Everyone! followed in 2013. ~ Jason Birchmeier, Rovi