If the perpetrator is a tenant, approach the landlord and request action. Contact the police about severe or threatening harassment or verbal abuse. Under the Public Order Act 1986, abusive or insulting behaviour can be an arrestable offence. If you decide to take private action in the magistrates' court, the court office will help you. You can also get advice from your local CAB, law centre, solicitor or Victim Support service.
Racial harassment is illegal.
Contact the police. Under the Race Relations Act 1976, council housing departments are required to take action in cases of racial harassment. Your local Racial Equality Council can give advice. Sweeping new powers, designed to protect tenants from intolerable behaviour, can also be used to drive out those whose lifestyle may simply offend the more narrow-minded neighbours. You can consult Shelter, another housing advice service, your local Citizens Advice Bureau, law centre or a solicitor.