It is every parent's nightmare: There are people out there — strangers living down the street, lurking near the local school, cruising town roads — who are looking for children. These predators want to snatch kids, entice them into a car or lure them into a home and use them to satisfy perverse desires.

But these fears, while not unfounded, do not begin to provide a full picture of the complex problem of sex abuse in the Twin States. A Valley News analysis of regional and national statistics, and interviews with sex abuse experts, law enforcement officials, victims and perpetrators suggest that the dimensions of the problem are not well understood by the public and that its solutions defy easy prescription by politicians.

According to those sources:

• Rates of sex crimes and sexual abuse in New Hampshire, Vermont, New England and the nation are generally falling, not rising. The exception is the rate of rapes reported to police in New Hampshire and Vermont, which has increased in recent years. However, the latest rates are still much lower than the national rate.

• Most sex offenders are not strangers. Instead, they are victims' family members and friends, neighbors and acquaintances. Nationally, strangers commit only one in 10 sex crimes. In New Hampshire, that figure is less than one in 30. In Vermont, it's less than one in 50.

• Many of those who sexually abuse children are themselves minors. Law enforcement records in Vermont and New Hampshire show that in four out of 10 cases involving victims younger than 13, the abusers are 17 or younger.

• The belief that sex criminals will almost certainly leave prison to find new victims is not supported by research. National studies show that many sex criminals have lower recidivism rates than people convicted of offenses such as burglary and nonsexual assault. While some hard-core sex offenders have 50 percent recidivism rates, others — particularly those who undergo treatment — have rates of 5 percent or less.

• Although a Vermont judge's decision in January to sentence a sex offender to a minimum of 60 days sparked a firestorm of debate, an independent study by a Vermont group and interviews with lawyers suggest that judges are not soft on sex offenders. If anything, they say, sentences have been getting tougher in some Twin State courtrooms.

• Even as politicians push for mandatory minimum sentences for sex offenses, prosecutors in both states agree that such minimums would prove a handicap rather than a deterrent. While more consistency in sentencing would build public confidence, they say, mandatory sentences would take away the plea-bargaining power used to resolve cases that might be hard to prove in court.

• Finally, interviews with perpetrators and victims suggest that it's dangerous to draw sweeping conclusions about the causes of abuse or its long-term consequences.

Sarah Kenney of the Vermont Domestic Violence and Sexual Assault Network said her network's groups — including the Upper Valley's WISE — reported almost 15,000 calls from victims of both domestic and sexual violence in 2005, an increase of 14 percent since 2004.

She said the increase could result from a rising number of attacks, more people discovering the service, or a combination of the two.

"The reality is that there are survivors of sexual violence in pretty much every room you find yourself in," said Kenney. "Survivors are everywhere."

But the overall decline in sexual abuse rates also suggests that at least some of the steps taken in recent decades — from educating the public and police to instituting prison rehabilitation programs — do help. "The problem (of sexual abuse) is still enormous," said Lisa Jones, a professor with the University of New Hampshire's Crimes Against Children Research Center. "But if we ignore the fact that it is going down, then we may miss the fact that some of the solutions we have now are actually working."