These are lightweight but durable and comfortable. They are lighter weight than some other athletic pants I've had, but they are not cheaply made, nor would I call them thin. They are simply lightweight fabric that is comfortable for much of the year. I wear them in Connecticut's winter, sometimes with another layer. I have a couple pair and use them for casual wear and to sleep in. The elastic cuff keeps the legs from riding up when sleeping in them and helps the legs drape nicely when wearing during the day. Elastic bottom cuffs are hard to find and I love these. The side pockets are handy to have too.