You want targets that people can see them and have a chance to achieve them. Be SMART:

• Specific: People appreciate a clear target - not a muddy one.

• Measurable: Use an indicator to measure it.

• Agreed: People are more likely to participate if they agree with the target.

• Realistic: - but challenging. Take account of what can be achieved, rather than purely hopeful.

• trackable: track all that contributes to
  the target.

Targets help make step by step achievements, rather than being daunted by the mountain to climb.

They are getting very popular with the UK government. With the moves to reduce regulations and replace them with more flexible instruments for change, targets are coming in from all angles.

The government targets for waste recycling, and for reductions in carbon dioxide emissions.