Massachusetts Eviction - Noncompliance with lease

[Donald M.]

I have a tenant I am considering starting the eviction process on for noncompliance with terms of the lease (smoking inside the property). I spoke with the tenant about it and she agreed not to smoke inside but has started again. What are the steps that I need to go through? I understand that I can serve a 30-day notice to vacate for violation of lease terms and if she does not move out within this time then I can begin the eviction process?

Also what happens if she stops smoking this time when threatened with this process, am I still within my rights to enforce the 30-day notice and then eviction even if she stops smoking (to prevent the situation when she starts smoking next month). Thanks!