As a dog owner you are fully and legally responsible for any harm or damages caused by your dog. If your dog bites a human, kills wildlife, damages property, causes a traffic accident, creates noise or other pollution, or is the direct cause of any other damage to the community, you may have to shoulder a substantial financial (if not legal) penalty. It is in your best interest then to always keep a vigilant eye on your dog in public and provide him with the obedience training and socialisation skills necessary to become a well-mannered and socially well-adjusted dog.
However, if you decide to keep your dog outdoors, it is important to consider how you'll ensure it receives the appropriate amount of human contact (particularly during those cold winter months in which we'd all much rather stay snuggled inside rather than playing fetch with our pals in the cold!). An option could be to enlist the service of a dog walker. Also, if you work long hours or are sometimes forced to take overnight trips, it may be useful to consider "doggy day care" facilities to ensure that your dog receives the TLC and companionship it will need in your absence.
While fleas are annoying, ticks can be deadly. The paralysis tick occurs mainly in spring and summer in Eastern Australia, and is found in long grass and the bush. Tick protection isn't necessary for all dogs and cats, and depending on where you live, may not be needed all year round – your vet can advise you on the situation in your local area. No tick preventative is 100% effective, so you still need to check your pet every day.
Puppy Roundworms can infect humans. To prevent this infection, puppies should be wormed regularly throughout their first year of life, and owners should be thorough with their own personal hygiene after having interacted with the dog. Tapeworms, Hookworms, and Whipworms can also infect dogs, and your veterinary surgeon can advise when to worm the dog.