'Stalking' (Mass. Gen. Laws ch. 265, §43) and 'Harassment' (Mass. Gen. Laws ch. 265, §43A)
Stalking and criminal harassment are very similar crimes in Massachusetts. Both crimes require "a knowing pattern of conduct or series of acts over a period of time directed at a specific person, which seriously alarms that person and would cause a reasonable person to suffer substantial emotional distress." You can be guilty of stalking or harassment no matter how you commit the alarming conduct, whether in person, by phone, text message, fax or otherwise.
Stalking is far more serious with graver punishment. Stalking is different from criminal harassment because it also requires that the accused "makes a threat with the intent to place the person in imminent fear of death or bodily injury." M.G.L. ch. 265, §43. Stalking is a felony. You can be sentenced to five years in state prison if you are found guilty of a first offense. A second offense carries a mandatory minimum sentence of two years in the ouse of correction or state prison. Stalking when there is a protection order or abuse prevention order in effect has a mandatory minimum sentence of one year in the house of correction or state prison.
Harassment is still a serious offense. Unlike stalking, a person does not need to make a threat to be guilty of harassment in Massachusetts. While it is a misdemeanor, harassment carries a maximum two-and-one-half year penalty in the house of correction.