Do you live in an area close to a major road or highway, train tracks, or flight path etc.? If you do, then outside noise is most likely an issue. Is it so bad that the time has come to do something about it? Besides moving to a quieter neighborhood, is there anything that could be done to lessen this type of noise pollution?
This is a good time to think about the areas of the house that allow more outside noise to seep in. Are there any cracks, or holes in the house that you could seal up? Although this may not eliminate the noise completely, it would certainly help.
There are, however, more drastic measures that could be taken. For example, if you have single-paned windows, consider replacing them with double-paned windows. Some advantages to double-paned windows are that they are sealed much better than single-paned, and have a space between the windows that can be a trap for unwanted noise.
Think about adding density to your walls with materials like sand, lead, or even more drywall. Soundproofing foam is also an option, usually shaped like an egg crate, it can be installed in the walls of your house.
In summary, while outside noise can be a huge disturbance to the peace of home, there are solutions.