Understanding stalking/offender dynamics, as well as the nature and extent of stalking, is essential to both the protection of victims and an effective criminal justice response to stalking. A study  based on interviews with 187 women in southeastern Pennsylvania who had been stalked by former intimate partners during the previous 5-years found that—
- On average, the stalker tended to be younger than his or her victim.
- Prior relationships between victims and stalkers included marriage (57 percent), cohabitation (25 percent), serious dating but not living together (24 percent), and casual dating (15 percent). Almost two-thirds of victims had suffered domestic violence in their prior relationship with the stalker.
- The length of stalking ranged between 1 month and 38 years, with a median of 12 months.
- Stalking had a serious impact on victims' lives. It brought on loss of weight, sleep disturbances and nightmares, anxiety attacks, depression, memory loss, and other physical and emotional symptoms. It left them with feelings of anger, fear, and helplessness; necessitated changes in their daily habits; and often resulted in damage to property, moving expenses, or loss of employment.
- Victims suffered as a result of leaving their intimate partners and again as a consequence of the relative scarcity of assistance and/or its ineffectiveness in discouraging the stalker and meeting the victim's needs.
[note 1] Brewster, M.P. "Exploration of the Experiences and Needs of Former Intimate Stalking Victims (pdf, 92 pages)." Final report submitted to the National Institute of Justice. Grant No. 95–WT–NX–0002, 1998, NCJ 175475.