Mark grew up Mennonite in North Newton, KS where he graduated from Bethel College in 1993 with a BA in Physics. From 1993-1995 he worked in Boulder, CO, directing a start-up Victim Offender Reconciliation Program and working on international issues at the Rocky Mountain Peace Center. He joined CPT in 1997 as a full-time worker and served on CPT's Hebron project for two-and-a-half years and with CPT's Chiapas, Mexico project for nearly a year. Between 2000-2001 he completed a Masters degree in International Peace Studies at Notre Dame University and then joined CPT's staff Support Team in the Chicago office as Administrative Coordinator.

He is married to best-friend and CPT co-worker Sara Reschly, and they have a son Elias who was born in 2005 and a daughter Eleanor born in 2009.