If you have a dog or a cat at home and want to introduce your bunny to them, first make sure you understand your resident pet's personality. If your cat or dog is rambunctious and enjoys rough play, you may not want to let your bunny loose when your resident pet is around.
You may begin introducing them by leaving the bunny to be in its cage while your resident pet is allowed to sniff out its new friend. A bunny in its cage may be brave enough to sniff back through the cage bars. When they have become friendlier, you may introduce them formally by cradling the bunny (for security) and allowing them to smell each other again. Ensure that your resident pet is able to understand your instructions such as "sit" or "down" or "no" when you introduce your bunny. Always be sure that your resident pet is being handled such that there will be no chance of it leaping at your rabbit and frightening it to death, or injuring it. Take care to trim the nails off your resident pet and always allow your bunny a quick escape back into its cage or home if it is afraid. Always reward good behaviour after their "meeting".
A few weeks of this and a bond may be established. However, NEVER leave them unsupervised even if their inter-species bond appears to be strong.
Rabbits also get along well with other animals such as hamsters and guinea pigs.