black_angel summed that up very well but I wan't to emphasize one of the points - 'a couple of females'. If you want to keep both sexes, get 2 females per male. Otherwise the male is likely to chase the single female constantly - resulting in stress and, indirectly, illness/infection and death. Dwarf gouramies are especialy susceptible to disease - it's not a good idea to stress them. Another good reason for getting 2 females is that females like company while males do not.
In fact, are you set on getting 2? It would be fine to get just one male.
As for getting 2 males, as long as they can establish territories they'll be fine. Generaly speaking, it's best for each male to have at least 10 gallons to itself and it's important that they are not competing for the upper layers of the tank with other fish if space is limmited (ie: in a 20-30 gallon tank you should not keep angels, other gouramies, hatchetfish danios or any other top-dweller with 2 male dwarfs). In larger tanks it's fine to keep other top-dwellers. Another hing to not is that it's a good idea to have tall-growing or floating plants in the tank and a current that is not over-powering coming from your filter. This should encourage the male dwarfs to set up territories far away from each other where they won't constantly be crashing and disputing territories or hierarchy.
