Here is a great resource for wiring job descriptions. Onetonline.org is a resource for both employers and job seekers from the US Department of Labour. You can find detailed job descriptions on most jobs and many other resources. This makes writing job descriptions much easier.

I use job descriptions as a tool for hiring new employees and for managing employee performance. You can read article and watch my video on how to write a job description here, and also download my job description form template.