attentive
     adj 1: (often followed by `to') giving care or attention;
            "attentive to details"; "the nurse was attentive to
            her patient"; "an attentive suitor" [ant: {inattentive}]
     2: taking heed; giving close and thoughtful attention; "heedful
        of the warnings"; "so heedful a writer"; "heedful of what
        they were doing" [syn: {heedful}, {thoughtful}] [ant: {heedless}]
Source: WordNet® 2.0