<PAGE>
 
                                                                    EXHIBIT 24.1
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 23/rd/ day of September, 1998.



                                    /s/ Thomas R. Ferguson
                                    ------------------------------------
                                    THOMAS R. FERGUSON
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.



                                    /s/ Mervyn L. Goldstein, M.D.
                                    ---------------------------------
                                    MERVYN L. GOLDSTEIN, M.D.
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 23/rd/ day of September, 1998.



                                    /s/ Ray E. Hannah
                                    ----------------------------------------
                                    RAY E. HANNAH
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.



                                     /s/ Roger H. Licht
                                    ----------------------------------------
                                    ROGER H. LICHT
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Paul C. Suthern and Anthony Vuolo and each of them,each with full
power to act as his true and lawful attorneys-in-fact and agents, each with full
power of substitution and resubstitution, for him and in his name, place and
stead, in any and all capacities, to sign the Annual Report on Form 10-K of
Synetic, Inc. for the fiscal year ended June 30, 1998 (the "Annual Report") and
to sign any and all amendments to the Annual Report, and to file the same, with
all exhibits thereto and all other documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorneys-in-fact and
agents full power and authority to do and perform each and every act and thing
requisite and necessary to be done as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents or any of them may lawfully do or cause to be done
by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.



                                    /s/ Charles A. Mele
                                    ---------------------------------------
                                    CHARLES A. MELE
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.



                                     /s/ Herman Sarkowsky
                                    -----------------------------------
                                    HERMAN SARKOWSKY
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/  day of September, 1998.



                                    /s/ Martin J. Wygod
                                    --------------------------------------
                                    MARTIN J. WYGOD
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 23/rd/ day of September, 1998.



                                     /s/ Albert M. Weis
                                    ----------------------------------------
                                    ALBERT M. WEIS
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele and Anthony Vuolo and each of them, each with full
power to act as his true and lawful attorneys-in-fact and agents, each with full
power of substitution and resubstitution, for him and in his name, place and
stead, in any and all capacities, to sign the Annual Report on Form 10-K of
Synetic, Inc. for the fiscal year ended June 30, 1998 (the "Annual Report") and
to sign any and all amendments to the Annual Report, and to file the same, with
all exhibits thereto and all other documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorneys-in-fact and
agents full power and authority to do and perform each and every act and thing
requisite and necessary to be done as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents or any of them may lawfully do or cause to be done
by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.

 

                                     /s/ Paul C. Suthern
                                    ----------------------------------------
                                    PAUL C. SUTHERN
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 23/rd/ day of September, 1998.

 


                                     /s/ James V. Manning
                                    -------------------------------------
                                    JAMES V. MANNING
<PAGE>
 
                                 SYNETIC, INC.

                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS, that the undersigned does hereby constitute
and appoint Charles A. Mele, Paul C. Suthern and Anthony Vuolo and each of them,
each with full power to act without the other, his true and lawful attorneys-in-
fact and agents, each with full power of substitution and resubstitution, for
him and in his name, place and stead, in any and all capacities, to sign the
Annual Report on Form 10-K of Synetic, Inc. for the fiscal year ended June 30,
1998 (the "Annual Report") and to sign any and all amendments to the Annual
Report, and to file the same, with all exhibits thereto and all other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents full power and authority to do and
perform each and every act and thing requisite and necessary to be done as fully
to all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that each of said attorneys-in-fact and agents or any of them
may lawfully do or cause to be done by virtue hereof.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as
of this 22/nd/ day of September, 1998.



                                     /s/ Bernard A. Marden
                                    -------------------------------------
                                    BERNARD A. MARDEN