Glue.

 Elmers Glue has been used by me for a long time. Two types are shown here-School Glue and Glue-All, but both appear to be the same thing in the way they can be used.
I think the first bottle came from The Works. It is basically a PVA type of adhesive but I have found it to be ideal for card construction.
It also seems to go a long way and never congeals inside the flexible bottle as some glues do.
Soon must look for some more and the bonus is that there is a distributor in the UK.