Reciprocity say life is about give and take.

Here’s how to use it at work, especially if you’re asking someone to do something and there’s nothing in it for them.  As in the other techniques, giving before you have a need to influence someone is vital.

How to do this without it necessarily costing you much time and effort – and no money – is in the Materials section

Here's a host of suggestions of types of giving that help to build trust and connection:

Reciprocity suggestions and actions