I have this set up for manhole inspections, with one to many...it works great. Initially, we were just relating a table within the mxd. That worked fine, but that has to be set up for every mxd.
The relationship class that Allison is talking about is the best bet if you want the related tables to be viewed by everyone. Like she said, you have to have an ID field in both your feature class and the related table that match up. In our case, we have a GISID field that I have in both tables. When you set up the relationship class, it asks you which fields you want to base the relate on. Make sure that the field types are the same! I had some issues with that initially.
For more info on it, try this.... ArcGIS Help (10.2, 10.2.1, and 10.2.2)