These cockroach traps are positively great. Made by Hoy-Hoy, marketed by "Kiwi care" not only do they catch cockroaches but they can catch mice as well and have seen the cockroaches do "press ups" in them. (or "push ups" as my E-mail friend Mike in USA tells me)

(1) The box you see that I purchased from a local shop contains three traps.
(2) You open a trap up, as you see one just in front of the box.
(3) Remove the brown waxed paper to expose the sticky bottom of the cardboard.
(4) Open up the pink packet, remove a smaller bag from it, and stick it to the middle of the sticky area about were you see it now, that smaller bag will attract the cockroaches, and the cockroaches and anything else will get stuck to the sticky surface.
(5) Fold up the sides so the trap is finished as you see it to the top right of the picture.
(6) Then place the trap were ever you think cockroaches are hiding, normally in a warm place, like near warm continuously run electrical appliances.

This procedure will not make you go dizzy unlike using some chemical spray (called BV2) for killing cockroaches, then a few weeks later you just get the trap and throw it out in the rubbish, what could be so kind to you? You don´t even need to hunt down dead cockroach bodies to sweep up and throw out.
Sometimes electronic items like televisions and video recorders go into a workshop with cockroaches in them, I found in the past that locking up a video recorders with a trap in a old non working refrigerator will catch the smallest of cockroaches.
I was told once that most houses will have cockroaches, But if you leave scrap food around they will have a picnic and will multiply fast, otherwise you would not normally see them.

To the right is my entire contents of what I purchased for my "Y2K Kit" back in the late 1999, You see there was an advertisement on television using a cockroach to encourage viewers to purchase items for a "Y2K Kit". All thou I did not think there would be a plague of cockroaches at the turn of the century for the year 2000, "CRC", "WD40" and other spray oil kills those cockroaches in seconds.

There is another type that I would recommend, where a tablet is enclosed in a plastic housing, the cockroaches bite the table then go away and die.