Frank Crijns studied composition at the Rotterdam Conservatory with P.J. Wagemans and K. de Vries.

His work as a composer can be divided in two parts:
1) Composing for soloists and modern music ensembles.
For example: Percussion ensemble Attacca, Andreas van Zoelen, Ensemble De Ereprijs, Dutch Ballet Orchestra, Trio Nu, Amsterdam Bridge Ensemble, Quasar saxophone quartet, AG-ensemble, Combustion chamber ensemble, Bl!ndman [4×4] saxofoon-kwartet, Diangelo Cicilia, Spectra Ensemble, Blast quartet: quartet, sextet & octet, Tetzepi big band, and many others.

2) Playing and composing contemporary and improvised music.
Frank Crijns has performed and composed with the bands Titanic Combo & Spelonk, Big Band Nieuwe Muziek, Positive Nuns, BLAST and more recently Betonfraktion.
Some of his collaborations are with Fred Frith, Elliot Sharp, Tim Hodgkinson, Pavel Fajt, Jacques Palinckx, Rhys Chatham, Phill Niblock, Bram Stadhouders, Aart Strootman among many others.
His work has been used for theatre and dance performances by T.r.a.s.h., the exhibition “Dressed (un)dressed” by visual artist Tineke Schuurmans, a performance with Dutch writer A.H.J. Dautzenberg and performances with visual artists/performers Bram Wiersma and Monique Smeets.
His solo works and works by his bands and projects have been released by labels such as BV Haast, Blowpipe Records, Vonk, Atma Classics, ReR, Kin Records, Cybele Records, Cuneiform Records, FMR Records and Pantheistic Records.