Some organizations do not allow the lay leader to give sacraments for example, but do allow them to perform most other portions of the service that are normally the responsibility of the clergy (e.g. giving sermons when the regular clergy are on vacation).
The Assemblies of God official position paper on Ordination states, "When necessary, the laity can perform all of the functions of ministry except those for which the State requires an ordained minister."
In The United Methodist Church the lay leader refers to the principal layperson in a local church, district or Annual Conference who represents and leads the laity in ministry.
It is an elected position, and the lay leader will serve on most church committees.
The Unitarian & Free Christian Churches of Great Britain have Accredited Lay Preachers who take services including rites of passage.