Dead leaves

Dead leaves on the edges of succulents are natural, especially for echeverias like the one in this picture. Brown and shriveled leaves of the edge of your succulent will eventually drop away, but if you'd like to remove them for aesthetics, they should come free with a gentle tug. If the stem or the leaves at the center of your succulent are looking unhealthy, that IS a problem. Take a look at the "Overwatering" "Underwatering" and "Sunburn" sections to figure out what's up.