We have several methods of measuring magnetic fields in the Milky Way.
We can study optical polarization, radio polarization, rotation measures
of pulsars and extragalactic radio sources as well as include Zeeman results.
Each of the above mentioned methods was at times used to make a model
of the magnetic fields of the Milky Way. However one or two of the data
sets by themselves cannot tell us the whole story. Any model of the magnetic
fields must be able to fit all the observational results. At the present time a
lot of progress has been made. We have increased our data bases in most
of the observational areas. However a robust model of the magnetic field of
the Milky Way has not yet emerged. We must possibly wait to the era of SKA.