To be sure that you have your mail delivered through certified means you need to read more from this site of the company that you want to deliver your letter or document to ensure that they have the service and is operational for you to use in the passing of information from you to the person you want these document to reach to.
Companies now do not have to worry how they will be able to reach their goals and objective because despite the fact they are not meeting as a staff member they can still be able to let the staff members work from wherever they are and if they are required to look at a hard copy document they will have the letter delivered to them by the person who sends certified mail, and they will have the chance to work on the document and when it is ready they can have the same company return the document to the other staff member and from this they will keep having the company operations done and be still been meeting the company targets. If you want to know more about this topic, then click here: https://en.wikipedia.org/wiki/Express_mail.