Place a large pot of water over high heat, bring to the boil and blanch the asparagus spears for 1 minute.
Refresh in iced cold water, drain and set aside.
Spread 1 tsp of tapenade down the length of one side of each prosciutto strip. Fold the other side over so the tapenade is trapped. Roll the prosciutto around the length of the asparagus, starting from the bottom and leaving