The parent sponsorship program has been temporarily paused until 2014-15. You have two options as of now. The easiest one is to ask your parents to apply to a Temporary Resident Visa (TRV) - also called as visitor's visa. With this visa, they can stay up to 6 months but can be extended for another up to 6 months once they are here. If you choose this option, your parents must show enough ties back to their country of residence so that the immigration officials are assured that they would return once the visa expires. Such ties include (but not limited to): One of the parent working, substantial property in the country of residents etc. Of course you would also have to provide your income statements to prove that you can take care of their stay here. It takes about 2 weeks to process TRVs
The other option is the SuperVisa. This program was introduced recently when the pause of the main parent sponsorship was paused. In this option, your parents are given a 10 year visa where they can stay in Canada for up to 2 years, which can be extended to another 2 years. They can come again any time within the 10 year period without applying for a visa again. You have to prove that you have enough income to support their extended stay in Canada + you have to purchase Canadian medical insurance for your parents. Since this is also not a permanent visa, your parents should show ties back to their country - just like the TRV. It takes about 3 months to process SuperVisa.
Hope this helps.
