Always write reference letters for employees honestly and credibly. Never state what you don't mean, and always substantiate praise with concrete examples. Depending on how well you know the employee, your reference can include examples of the employee's commendable performance as well as of the employee's laudable character traits. Either way, use a basic pattern of organisation to showcase the employee's strengths.
State how and for how long you have known the employee. Include the reason you are writing the letter. For example, "Mary Murphy has worked as a project manager under my supervision for more than five years. I am pleased to provide this letter recommending her for a project management position in your firm."
Provide specific information about how the employee's character traits positively affect performance at work. For instance, "Mary's eye for detail and exceptional documentation skills have kept projects moving relatively issue-free. Her ability to remain cool and collected under pressure has calmed many a flustered client and co-worker."
Mention the employee's specific contributions to the workplace. For example, "Each of the ten projects that Mary has managed for our firm has come in on schedule and under budget. Her client service has resulted in repeat commissions from three clients."
Highlight any special qualifications that make the employee different from others. For instance, "Mary is not only an accredited sustainable design professional, she teaches a course on the subject at our local community college."
Summarise the employee's strengths and close with an unequivocal recommendation. For example, "Mary is dependable and capable in all aspects of project management. I hold her in the highest esteem and recommend her unreservedly."
Use superlatives sparingly, if at all. Instead, relate examples of exceptionality. It is neither good to be too brief nor rambling. Be succinct, direct and substantive. Do not mention the employee's age, religion, race, ethnic background, marital status or disability. You may offer to provide additional information at the end of the letter. If you do, provide a phone number or e-mail by which the letter recipient may reach you. Check your letter for spelling and grammar mistakes before giving the employee a final copy.