To aid what Jack has already said, use the DMV to get a better idea of whether or not the index is actually used...and remmber to keep in mind that these statistics are kept as a running total of since the last time the SQL service was restarted. So if you recently restarted your server, your results may be skewed and you might want to wait a longer period of time before making any decisions to drop an index.

A script I like to use (and I believe it came from SSC) is:SELECT ROW_NUMBER( ) OVER ( ORDER BY b.user_lookups DESC ) RANKING ,

DB_NAME() DBName ,

OBJECT_SCHEMA_NAME(a.object_id) + '.' + OBJECT_NAME(a.object_id) AS objectName ,

a.name ,

CASE WHEN is_unique = 1 THEN 'UNIQUE '

ELSE ''

END + a.type_desc [IndexDesc] ,

b.user_seeks ,

b.user_scans ,

b.user_lookups ,

b.user_updates ,

b.system_seeks ,

b.system_scans ,

b.system_lookups ,

b.system_updates ,

b.last_user_seek ,

b.last_system_seek

FROM sys.indexes AS a

LEFT OUTER JOIN sys.dm_db_index_usage_stats AS b ON ( a.object_id = b.object_id

AND a.index_id = b.index_id

AND b.database_id = DB_ID()

)

WHERE a.name IS NOT NULL

AND OBJECT_SCHEMA_NAME(a.object_id) <> 'sys'

AND ( b.user_seeks = 0

AND b.user_scans = 0

AND b.user_lookups = 0

)