Measuring and evaluating user and other stakeholder engagement with the library and its services is fraught with difficulties. Which indicators are appropriate and worthwhile? What levels of performance against these would be considered good? If measuring external engagement should you also measure employee engagement with the library purpose, its services and users? Having engaged users but disengaged staff is unlikely to provide the environment where the library service fulfils its engagement ambitions.

Despite these difficult questions, it is important to find a meaningful way to measure our progress in increasing levels of engagement. This is important for two reasons:

• ■ In most library contexts there is a need to show through measurement that resources and funding have been spent and used wisely.

• ■ We need to learn from our past activities. If marketing activities are not closely evaluated how will we know what works and what does not, with the consequent implications and advice for future activity?

Even though a library's goals may not be fully reached, progress towards achieving them may well be sufficient to constitute success when routes to engagement are long and unpredictable. The most effective and efficient engagement and marketing programmes always learn from the successes of previous campaigns: evaluation is part of that learning. Evaluation of current engagement activity is the starting point in the next round of engagement planning.

These are some of the important criteria that can be used to judge qualitative or quantitative success:

• ■ Effectiveness. How well did you achieve what you set out to achieve?

• ■ Efficiency. How well did you use your resources in pursuit of your goals?

• ■ Benefits. What can you point to as achievements and positive changes, either planned or accidental, as a result of your engagement programme and campaigns?

• ■ Costs. What were the costs of the engagement programme and its overall value for money?

One way to structure your evaluation is to reflect on the processes that deliver or contribute to change over time:

• ■ outputs: what you do

• ■ outcomes: what happens as a result, what did they do, feel, sense, think, value or understand