N 2 O and the NO y species are among the most important trace gases in the atmosphere. They play crucial roles in global warming and ozone chemistry. The quantification of a global correlation between NO y and N 2 O will help to better understand the upper troposphere and lower stratosphere. In my presentation, I will first introduce previous studies of NO y -N 2 O correlations and then discuss NO y -N 2 O correlations derived using ACE-FTS data products. My results will be presented for five different latitude ranges, which are 90-60N, 60-30N, 30N - 30S, 30-60S and 60-90S. For each latitude band, the correlations between NO y and N 2 O will be shown as a function of season (MAM, JJA, SON, DJF) and pressure (<10mb, 10-35mb, > 35mb). Polynomial fits are obtained in the region where the mixing ratio of N 2 O is between 100 and 300 ppbv. Results for 90N - 60N will be discussed in detail, including comparison with previous studies.