Ever had to write a letter of resignation and yet stay in the same company? Here's how to write that letter leaving one site while getting that awaited promotion at another site. Thank the company for the opportunity to grow with them and all the things that you've learned that you will use at your new site. Compliment your supervisor by letting them know that without their guidance and advise you would of had a hard time learning how to organize your multitasking duties. Also thank your supervisor on teaching you how to be an asset to the company. Allowing you the opportunity to always handle the important cases. And advocating on your behalf when needed. Overall, thank the company for the opportunity to enhance your career. And you will give them the same dedication at your new position as your old one.