There are many strategic policies and operational methods to encourage internal and external collaboration. Traditional approaches such as supporting travel to conferences elsewhere or hosting conferences at an institution (as mentioned), research grant funding that does not penalize multiple reseachers, and having an organizational/departmental culture that includes an expectation of synergistic collaboration. In recent years there seems to have been an increase in collaboration in some disciplines and there have been papers published about the increase in coauthorships. I believe hiring colleagues who are interested in collaboration is important, and that the tone of the intellectual scholarly endeavors is often established by academic department leaders.