George and Lennie have a dream. They want to have a ranch of their own some day. Instead of working for other people as they do now they'll be their own boss. What's more, Lennie will get to look after the rabbits, something he dreams about more than anything else.
For the two men, the dream of owning their own farm represents freedom. They see this as their only chance to break free from an itinerant lifestyle in which they travel from place to place in search of work, only to end up with nothing to show for it. George recognizes that in this business the only people who make any real money are those who own the land, not those who work it. He also understands that having a ranch of their own will provide Lennie with a haven of peace and security from a world he doesn't understand and which doesn't understand him.