Yes, it can work depending on what you are using it for. Despite what another member posted, the most recent study I am aware of appears to validate the concept of aromatherapy.
A study published just a few months ago in the American Chemical Society`s Journal of Agricultural and Food Chemistry, exposed lab rats to stressful conditions while inhaling and not inhaling linalool, which is a fragrance found naturally in lavender, mint, coriander, bergamot, lemon, mango and many other fragrant plants. After inhaling linalool, the rats which were exposed to stressful conditions had stress-elevated levels of neutrophils and lymphocytes return to near normal levels (both neutrophils and lymphcytes are key parts of the immune system).
In all, linalool is found in over 200 species of plants, mainly from mints, scented herbs, laurels such as cinnamon and rosewood, and citrus fruits. It is also found in some birch trees and other plants and has even been found in some fungi. The majority of the fragrant plants which contain linalool are noted for having a floral scent with a touch of spiciness.
The scientists also found that inhaling linalool reduced the activity of more than 100 genes that are normally significantly elevated in stressful situations. The findings could form the basis of new blood tests for identifying fragrances that can soothe stress, the researchers say. While linalool has been one of the most widely used substances to ease tension and emotional stress, until the new study the ways in which linalool affected the body had been an unsolved puzzle to scientists.
Aromatherapists have long believed in the power of fragrance to lower stress levels - and aromatherapy for stress relief has been popular for ages, although until the Japanese study there`s been little scientific evidence to support it. Now it appears that just like the advice our mothers and grandmothers gave us to "eat an apple a day to keep the doctor away", the advice "stop and smell the roses" from time to time may be yet another popular bit of old time wisdom that rings true.