It helps, it didn't completely eliminate the odors but it does make a difference. I tried it on my daughter's PE shoes and a pair of sneakers I washed that didn't dry, which resulted in a small odor. I really dislike the smell of this spray; it reminds me of soap from a public restroom, a strong and artificial fragrance. The scent is mostly unnoticeable when it dries, but it wasn't pleasant when spraying the shoes. For the shoes that had a slight scent from not drying completely after a wash, I had to treat them, let them dry, and repeat twice before I noticed a difference. There is still a slight smell, but it's not too noticeable. For her PE shoes, I also had to repeat the treatment, but they smell fine now. A pair of shoes with a stronger odor may need multiple treatments and may not completely go away with just this product.