Life revolves around three social spaces: personal private space, public or work space — and what this article defines as "courtyard" space. Each of these spaces can be associated with a certain type of relationship: friends, allies and, in the courtyard, "chums." Personal space is occupied by friends, relationships where acceptance is close to unconditional. The public space, by contrast, is the social sphere of highly conditional relationships. These relationships come and go, lasting only as long as they help both parties achieve valued goals. Colleagues, clients, prospects, acquaintances, customers, teammates, bosses, peers, classmates and subordinates are all members of conditional relationships, and they all occupy the public social space. In the business world, colleagues, peers and other contacts work together as what we call allies when it is in their mutual self-interest to do so. They can easily oppose one another in one area of work while agreeing in another. One might feel anger and hostility toward a business ally because he or she works against one's self-interest, but one should not feel a sense of betrayal. Only friends can betray. But there's a third kind of business relationship that's often overlooked: the relationships in between friends and allies — in other words, business relationships with people you enjoy being with. This article calls these people chums, and asserts that their importance too often goes unnoticed. Chums occupy a space that is not quite the same as the one inhabited by either friends or business allies. The social courtyard is the space for turning allies into chums. Dale Carnegie's best-selling book How To Win Friends & Influence People is not, in fact, about making friends in the sense of forming unconditional relationships. It is instead a practical classic on the art of cultivating chums — of inviting business allies into your courtyard while keeping them out of your kitchen.