Superimposing Graphs by Importing Data

I have two different MATLAB files where I end up with a graph of drag force plotted against a dimensionless parameter. I would like to plot the results of both graphs in one graph as the ranges of the x and y axes are the same. Is the easiest way of doing this to save the results going into the graph from one of the graphs as some kind of data file and then import it over and introduce it into the graph in the other file?

Let me know if it's not clear what I am trying to achieve and I can explain further.