The Principle of Subsidiarity in a Nutshell
From Budziszewski on Subsidiarity:

As [Pope] Pius [IX] explained, what pushed the principle of subsidiarity to the forefront was the crisis in civil society brought about by the industrial revolution. For a time it seemed as though the middle rungs of the ladder might be crippled or destroyed, leaving nothing but the vaunting state at the top of the social scale and the solitary self at the bottom. Collectivists and individualists made strange alliance to cheer this holocaust of the little platoons. The principle of subsidiarity reaffirms the social design of the species, corrects both its individualist denial and its collectivist perversion, and champions the rights and dignity of all those in-between associations which, if only allowed, will take root and flourish, filling the valley between State and Self with fruit and color.

Now that's a real "third way."