The present invention relates to sulfone derivatives of formula (I):
Ar—SO
2
—CR
2
R
3
-L-N(R
1
)
2
I
wherein Ar, L, R
1
, R
2
and R
3
are as defined herein, and pharmaceutically acceptable salts and N-oxides thereof, useful in the treatment of a condition which is susceptible to treatment by modulation of 5-HT
7
receptor activity, such as depression or a sleep disorder.