It's important to pay attention to how trees affect eachothers growth.  Trees growing close together will compete for light by growing away from the shade of other trees, towards open sunlight.  Trees tend to grow away from other trees, often times leaning far over a house to get more sunlight. This is easily prevented by pruning adjacent trees, opening up areas where sunlight can be used to balance a tree's growth.

If a tree gets sunlight from all angles it's less likely to compete for light by growing off-center, and over a building.

A typical landscape does not have the capacity to sustain very large trees, nor do homeowners want the added risk.  Pruning can be used to keep a trees close to a home from growing too large and becoming hazardous.  As a rule, trees heal best when the wound is small.  This means that pruning of main, or 'leader', limbs should be done as early as possible, but any time is better than never.  Maintenance pruning ever few years can keep the canopy's size in check; removing small, unwanted limbs will prevent the tree from growing at a normal rate.