Change things UP! Try something different. If you're doing the same workouts every day every week, try a new combination of workouts in different orders on different days.
Also, on your calorie intake, try going towards the high end one day and then the next couple days go towards the low end. So for instance I'm supposed to take in anywhere from 1250 to 1550 a day. But if I eat approximately the same amount every day my body starts to get used to it. It's strange but true. Somehow our bodies get used to what we'really doing so we have to switch every thing up! So what I've done during plateaus is eat very restricted for several days and then "cheat" a little for a day or two and then go back to my more balanced routine.
Our nutrition and our fitness. SHAKE THINGS UP! And then come back to your routine later. It's worked for me before many times! And remember even in you're workouts themselves we need to keep it exciting and to some degree keep pushing our bodies to learn new things (instead of the same ol treadmill workout every day of the week try switching things up with some strength training. )
When it comes to strength training I can't emphasize enough how much this will help BLAST through plateaus because as we challenge our muscles it forces us to burn more calories. A combination of cardiovascular and strength training is even better. But try doing one muscle groups one day and then another on a different day so that you can alow your muscles to strengthen. And you don't need to worry about bulking up as long as your doing more reps with less weight. This will help you get lean. And lean is good!!!
One last thing. Remember that even sometimes when the scale isn't moving there are things happening inside that doesn't show up in the numbers.