Mathews focuses on Antigonish and Mondragon as two major attempts to put the ideas of distributism into practice. Although he had other examples to choose from, these two movements illustrate his central thesis: distributism only works when people have jobs (that is, work) of their own.
In the early 20th century, Antigonish was a movement of consumer co-operatives in Nova Scotia which flourished for a time, but ultimately failed. Although Mathews finds much to praise in their work (and plenty of consumer co-ops flourish today), he uses Antigonish to illustrate how the basic agency dilemma will weaken any co-operative that operates only on the consumer level. You may have a food co-op, but if you hire outside managers to run it, there's nothing particularly co-operative about their incentives. They may as well be working at the mall.
In contrast, Mondragon is a worker co-operative. This co-operative (really a co-operative of co-operatives) is altogether the seventh largest corporation in Spain. Big business? Hardly. Mathews examines the intricate mechanisms by which a worker in a Mondragon factory has a real voice in how his shop is run, a real stake in the success of the whole enterprise, and a real safety net for keeping at work, not getting welfare payments.
By the way, THE DISTRIBUTIST REVIEW has reviewed the encyclical Caritas in Veritate here. The review is by John Medaille, and it is one of the best I have seen.