Do you believe that every child should have two parents in their life?

It depends on the parents. Until about a year ago I was thinking that adopting as a single parent would be my only option. I was raised by my mother and grandmother - better than my father. I think two parents is ideal but it's better to have one good parent than two crappy ones.

I think if both parents are good parents, two is ideal. I think if one of the parents is a very bad parent (dangerous, cruel, uncaring... etc.), the child is always better off being raised without that parent as an influence in their life.

I don't know much about this, and I think I could easily say something that would sound disagreeable to some, but I'll throw in a few thoughts.

I think it is important there are people that care for the child and treat it well. I can't see that it is so unlikely that a single parent would be able to care sufficiently for a child, that I would say that there needs to be two parents.
As already pointed out, if one parent treats the child badly then having only one (good) parent would be better.

Others can answer better than I whether feelings of different for having only one parent or feelings of being unwanted by the parent that is not there, are unavoidable.

Looking outside western culture, I have heard Christopher Ryan speak of interesting examples of different parenting cultures. One example is societies in which the beliefs about conception divides paternity onto several men, and another is a society in which the child is raised by the mother and her family.
If the children in these societies are not generally unhappy and live bad lives, then the societies are examples of children not needing exactly two parents.

Mostly it benefits the parents when there are two to divide the load of responsibilities.

Other than that, a single parent with adequate resource can provide enough attention and care necessary to raise a child.

Well, studies state that children develop better with two parents, specifically a father. So, I would say so, yes.

I believe a whole lot of the social problems in the US are because of the breakdown of the family. Parents should be taking the responsibility for raising their own children, instead of farming them out to schools and after school care centers, while they chase the almighty dollar.
Of course, two parents are infinitely preferable to a single parent family, if it is a safe and healthy (or reasonably so) environment for the children.
As a single parent who raised a girl child, I am also of the opinion that a family with both male and female role models in a home is preferable. I was far from any support and I found I was ill prepared to raise a girl child. I had been raised as a boy (obviously) and had no idea how to handle many of the emotional things a girl child growing up, goes through.
This is not a put down of gay families, but it should be a consideration to have both genders involved in raising a child.

I grew up with one parent, and I'm not sure, but it's better to be raised by one happy parent than two unhappy ones. If one parent; like my father, commits domestic violence, the relationship shouldn't go on for the sake of the kids.

Yes a father and a mother
Not two dads

It really depends on the parents, as others have stated. For instance, let's say that you find out that, god forbid, your partner is a pedophile. Under no circumstances would that be a good environment to raise a child in as that child could be in danger.

Sometimes, NEITHER parent should be raising a child. In a case like this, the child would be better of placed into the care of someone else.

wow, im shocked by the results, i would have better off without my dad when i was growing up and im surprised so many people feel it has to be a straight couple in order to be a suitable environment

I was also only raised by my mom since I was 7.

I think that every child should have GOOD rolemodels of both genders in his life. That's what matters.

I believe it's ideal, but not necessary, as said above.

As a woman and potential Mother, I feel as if it would be most beneficial to my kids to have them with a strong father figure in their lives. Although I truly do believe that a Mother can raise children just fine by herselff, I just see it as simply better to have the father around.

I think it's ideal, but not necessary in every situation.

At least two.