The fox, the goose, the grain, and the dog

This time, the farmer has to transport a fox, a dog, a goose, and some grain across a river. He has a boat which can carry himself and either the fox, dog, goose, or grain. If the farmer isn't present, the fox cannot be left with either the dog or the goose, or both. If need be, the goose can be left with the grain provided the dog is present because the dog will guard the grain and won't eat the goose. Help the farmer cross the river.

(This puzzle is from The New Puzzle Classics by Serhiy Grabarchuk, Sterling publishing company, New York, 2005.)