Spaying and neutering have definite health benefits for the pets that undergo the procedures. However, the procedures are not without their pitfalls. Surgical sterilization, as the name implies, involves anesthesia and surgery. Surgery may be painful. Complications, although rare, can occur. And, significantly, the availability of surgical sterilization has not eliminated pet overpopulation and the attendant euthanasia of perfectly healthy cats and dogs.
Vets and animal lovers have been dreaming for years of a simpler way to prevent pet overpopulation. Sadly, that dream is nowhere near reality.
However, a philanthropic organization has taken an important first step towards the goal. Following the successful example of the Ansari X prize, the organization is motivating people to find a solution to pet overpopulation using a tried-and-true tactic. They are offering a huge wad of cash to the person or group that develops a simple, safe, easy to administer, single dose pet sterilization technique.
You can read more about the prize (called the Michelson Prize) here.
The reality of such a technique is still far away. However, I suspect that the Michelson Prize help motivate researchers to achieve the goal.