For those who don't know the basic background, Mastercard was a member-owned association that focused on payment processing and franchising its credit and debit card brands and, later, related consulting projects.
In the 1990s, it began converting to a more independent share-based business, though still owned by the same banks, and this year it took a stride toward further independence by IPO'ing the majority of the voting shares.
Mastercard was the dominant US card for many years, but is now a distant second to Visa in the US and in most other markets. If you look at market share and spending around the world, in most places you'll see Mastercard or its affiliates with about half the market share of Visa and you'll see Mastercard spending about half as much as Visa on building their market.
It's been a nice, tidy system for a while that has allowed these companies -- both of which are very lean and consist primarily of brand names and computer networks -- to prosper. Visa remains a private concern, though there has been talk since the MA IPO of Visa doing the same.
Read more at: Deconstructing Mastercard