Growing up in a suburb of Concord, NH, Mark wrote songs as early as elementary school, followed by performances in original rock bands and jazz study at the Concord Community Music School.  He received a BA in Music Performance in 1992 from the University of New Hampshire, where he played classical and jazz piano and apprenticed with such adjunct professors and visiting artists as Clark Terry, Phil Woods, and Jimmy Heath.  He moved to Boston, continuing his studies at New England Conservatory, receiving a Masters of Music in Jazz Studies in 1994, working with such teachers as Bevan Manson, Paul Bley, and John McNeil, supplementing his education since then by studying with jazz gurus Kenny Werner, Hal Crook, and Charlie Banacos.

Following a move to New York City in the mid-90's to immerse himself in the hotbed of music that is Manhattan, and a subsequent return in 1997 to become an Assistant Professor at Berklee College of Music and to teach at his alma mater, UNH, Mark released his debut CD, First Look (1997), a piano trio date featuring Steve LaSpina on bass and Jeff Hirshfield on drums.  Mark followed this release with a shift in artistic direction, continuing on the path of jazz, but also incorporating the singer/songwriter influences of his early years, such as Elvis Costello and Steely Dan.  This direction culminated in a collection of original music, Different Songs (2000), featuring Mark as principal vocalist as well as producer/keyboardist.  Other Voices (2003), Shilansky's third CD as leader, marked a return to jazz, Latin-jazz, and long-form (occasionally free-jazz) compositions, all featuring the voice in some way, and featuring the vocal work of Luciana Souza, Lisa Thorson, and Paul Stiller of "Vox One".  

Join the Club (2007), has been described as "21st Century Space-Age Bachelor Pad Music," and features original compositions and Latin-Jazz renderings of jazz standards and contemporary pop tunes by the bands Police and the Cardigans, and features saxist Donny McCaslin, trombonist Jay Ashby, and vocalist Kim Nazarian. Of this CD,  Jon Garelick, Boston Phoenix, says "Shilansky knows how to make every moment engage, [with] long arcs of melody as he works through the chord changes... this 'club' is one anyone would be happy to join."  

Fugue Mill (2014) features violinist Sara Caswell, guitarist Eric Byers, and mandolinists Joseph Brent and Bryce Milano in a program of mostly original music influenced by Jazz, Bluegrass, and Celtic Music.
All throughout this creative career as a pianist and composer of his own material, Mark has been a consistent presence as a sideman.  A tenure throughout much of the 90's as a member of the Luciana Souza quintet led to his almost ubiquitous presence as an accompanist of vocalists, such as Lisa Thorson, The New York Voices, Kris Adams, Carolyn Leonhart, Rebecca Parris, and Patrice Williamson (for whom he has written copious arrangements, and produced her CD, Free to Dream). Mark plays piano and contributed an original composition "All in My Heart," to NYvoices soprano Kim Nazarian's debut solo CD, "Some Morning."  He played piano and contributed arrangements and an original song, "I have found", on the debut release by rising star vocalist Robin McKelle, Never Let Me Go.  Mark is a strong presence on vocalist Chris Humphrey's debut CD "Nothin' But Blue Skies," featuring Martin Wind (bass) and Matt Wilson (drums), and for the last four years has been the pianist and occasional arranger for the vocal jazz group Syncopation, appearing on the band's CDs and accompanying them on tours of the US and Japan.  
Shilansky has kept active as a sideman with instrumentalists, as well, notably with guitarist Steve Kirby (playing piano and organ on his North Light CD), trumpeter Kenny Wheeler (with concerts at the Regattabar and New York's Birdland), and on drummer David Jamrog's Visions, a collective group featuring saxist George Garzone.  Also, increasingly, Shilansky is in demand in the recording studio as a Producer/Arranger as well as a performer with a growing list of artists (singer/songwriters as well as jazz artists), having served in this capacity on CDs by Kaye Kelly, Celia Slattery, Dana Edelman, Christina Watson, Lauren Wool, Allyssa Jones, and Michelle Mailhot. He is co-producer/arranger and pianist on David Thorne Scott's 2021 release "Thornewood," which features a blend of jazz and Americana and performances by Paula Cole, Peter Eldridge, Walter Smith III, Jason Palmer, and Sara Caswell.

Recently, Shilansky has entered the world of podcasting, with his Mark Shilansky's Talking Music podcast, available on itunes, and featuring interviews with a diverse spectrum of local and international great musicians.  

Mark serves as an Associate Professor at Berklee College of Music, where he has taught since 1997, teaching Ear Training, Arranging, Harmony, and Ensembles.  He also has taught Jazz Piano and Ensembles at the University of New Hampshire, since 2002, and from 2009 to 2011 taught these subjects at University of Southern Maine. In addition to these institutions, his compositions and arrangements have been performed at the University of Wyoming, Bowling Green University, and All-State Festivals in Nevada, Maine, and New Hampshire, and he has taught clinics and residencies at the above-named All-State festivals, as well as Duquesne University, Fort Hays State University, University of Idaho at Moscow, and Eastern Tennesee State University.