Conversation so far:
what was Horace Plunkett trying to accomplish?
Cooperatives and Plunkett were denounced for supposedly ruining the dairy industry but the movement caught hold, with the mass of farmers benefitting.
what did he do to help the movement?
Plunkett and his colleagues including the poet and painter George William Russell (AE) made a good working team, writing widely on economic and cultural development.
what project was he involved in?
As early as 1894, when his campaign reached a size too big to be directed by a few individuals, Plunkett founded the Irish Agricultural Organisation Society (IAOS).
what did this society do?
Robert A Anderson acted as secretary, with AE and PJ Hannon his assistants.
IAOS soon became the powerhouse of co-operation, with 33 affiliated dairy cooperative societies and cooperative banks.

Question: how was this beneficial?
Self-contained rewrite: how was the Irish Agricultural Organisation Society (IAOS) beneficial?