Obvious travel safety tips will serve you well in Jaco:

 Don't leave anything in your rental car over night (or doing the day unattended) - esp. surf boards or camera equipment.

 Don't leave anything on the beach unattended - even flip flops.

 Don't go onto the beach after dark.

Jaco has a large police presence on the street (only one main avenue in town) and is generally a very safe place for visitors day or night.

*** Water safety and common sense are very important in CR***

 While Jaco beach is a great place to relax, soak up the sun and watch local surfers - be very careful of riptides if you decide to go for a swim.

Every year there are a good number of people who drown due to riptides and heavy surf.  If you are not an experienced swimmer in good shape or a surfer/boogie boarder, do not swim out past the breakers or to areas where you cannot touch the bottom.

 If caught in a riptide, try to stay calm, conserve energy and try to get a surfer's or lifeguard's attention.  DO NOT try to swim back to shore - instead, swim parallel to the shore as only a small area is effected by the riptide. http://ww2010.atmos.uiuc.edu/(Gl)/gui...