The position I hold is one of inclusivism, which adopts the understanding of the "anonymous Christianity", a term coined by Catholic theologian Kahl Rahner, who describes the idea as follows:
Anonymous Christianity means that a person lives in the grace of God and attains salvation outside of explicitly constituted Christianity — Let us say, a Buddhist monk — who, because he follows his conscience, attains salvation and lives in the grace of God; of him I must say that he is an anonymous Christian; if not, I would have to presuppose that there is a genuine path to salvation that really attains that goal, but that simply has nothing to do with Jesus Christ. But I cannot do that. And so, if I hold if everyone depends upon Jesus Christ for salvation, and if at the same time I hold that many live in the world who have not expressly recognized Jesus Christ, then there remains in my opinion nothing else but to take up this postulate of an anonymous Christianity.
At this point, a distinction should be made between the inclusivism of anonymous Christianity and what we know as pluralism. Whereas pluralism asserts that there are many, or possibly infinite sources of salvation, inclusivism asserts that all who are saved are saved through Christ. The Christian is saved through Christ, the Hindu is saved through Christ and the even the atheist is saved through Christ. In this respect, I find Christian inclusivism to have a higher Christology than exclusivism because Christian inclusivism fully appreciates the scope of Jesus salvific influence. While the exclusivist believes that Jesus can only redeem a small fraction of humanity, the Christian inclusivist recognises that Jesus is both able and willing to reconcile much, or even all of the cosmos to himself.
I should point out that it is possible to be an inclusivist without being a universalist, although I believe that the most nuanced universalists will adopt an inclusivist position. When I get a chance, I shall explore the principles that support not only Christianity outside of Christendom, but how the whole creation (indeed, not merely humans) will eventually come to understand Christ and their Saviour.