Interest groups may initiate their own policy proposals, perhaps in association with members of Congress or their staffs who share the same interest. Interest group staffs often bring valuable technical knowledge to policy formation, as political information about their group's positionon the issues. Because Congress members and their staffs value both kinds of information, interest groups can often provide the precise language they desire in proposed bills and amendments . Thus, interest qroup staffs often augment the work of congressional staffs. Interest groups also provide testimony at congressional hearing as well as technical reports and analyses used by congressional staffs.