procedure ExecNewProcess(ProgramName : String; Wait: Boolean);
var
  StartInfo : TStartupInfo;
  ProcInfo : TProcessInformation;
  CreateOK : Boolean;
begin
    { fill with known state } 
  FillChar(StartInfo,SizeOf(TStartupInfo),#0);
  FillChar(ProcInfo,SizeOf(TProcessInformation),#0);
  StartInfo.cb := SizeOf(TStartupInfo);
  CreateOK := CreateProcess(nil, PChar(ProgramName), nil, nil,False,
              CREATE_NEW_PROCESS_GROUP+NORMAL_PRIORITY_CLASS,
              nil, nil, StartInfo, ProcInfo);
    { check to see if successful } 
  if CreateOK then
    begin
        //may or may not be needed. Usually wait for child processes 
      if Wait then
        WaitForSingleObject(ProcInfo.hProcess, INFINITE);
    end
  else
    begin
      ShowMessage('Unable to run '+ProgramName);
     end;

  CloseHandle(ProcInfo.hProcess);
  CloseHandle(ProcInfo.hThread);
end;

http://www.delphicorner.f9.co.uk/articles/wapi4.htm

Using CreateProcess to Execute Programs

Delphi