Stake patriarch
A stake patriarch's responsibility is to give patriarchal blessings. These blessings are an important part of every young latter day saint's life and serve as a kind of life road map. Every stake has at least one patriarch (except in the event of a sudden death or move out) or if need arises more than one. Once a patriarch is ordained he cannot be released. He can, however, be given nonfunctioning status if health prevents him from serving, he goes on a mission or moves out of the stake. In that case he can still give blessings to lineal descendants.
Extent and Limits of Authority
A patriarch can only give blessings to members of his stake and his descendants. In the past they could also give blessings to siblings and, in some cases, family friends. In the event of a language barrier, the patriarch in a neighobing stake speak the blessing. Also if a stake lacks a patriarch (as occassinally happens when one moves out or dies suddenly) or likewise, when a blessing is needed in a district, then a neighboring stake's patriarch may serve.
Stake patriarchs are men who are faithful in the church and patriarchs in there own home who may or may not have had much leadership experience in the church chosen on worthiness.