Tweaking Alan's code, I can reduce the reads by half by reducing the length of the code. 🙂

WITH uqvals AS

(

SELECT ID,

MIN(DateOpen) DateOpen,

MAX(DateClose) DateClose

FROM @table

GROUP BY ID

)

SELECTID,

[Desc] = REPLACE(REPLACE((SELECT '|'+[desc]+'|' FROM @table t WHERE uv.ID = t.ID FOR XML PATH('')),'||',','),'|',''),

DateOpen,

DateClose

FROM uqvals uv;