nationally, nicholls has served as a member of the commission on the marriage canon from 2013-2016, the co-chair of the anglican-roman catholic dialogue in canada from 2012–present, a member of the faith, worship and ministry committee of the anglican church of canada from 2011-2016, first a member and the chair of the standing committee on religious orders of the anglican church of canada house of bishops, the chair of the primate's theological commission of the anglican church of canada from 2008-2010, a member of the task force on the role of the primacy in the anglican church of canada from 2008-2010, co-chair of the ecumenical health care network of the canadian council of churches, a member of the canadian christian jewish consultation from 2005-2008, co-chair of the national muslim christian liaison committee from 2005-2008, staff resource to the human life task force from 2005-2008, member of the interfaith task group of the canadian council of churches from 2005-2008, staff resource to the faith, worship and ministry committee of the anglican church of canada from 2006-2008, a member of the canadian anglican-roman catholic dialogue from 1989-1998, chaplain to church house, national office of the anglican church of canada, a general synod delegate in 2004 and staff to general synod in 2007, a member of the partners in mission committee of general synod in 2005 and a member of the windsor report response task force of the anglican church of canada in 2004-2005.