diff --git a/UApp.pas b/UApp.pas
index 4fc7b88..a73d0e3 100644
--- a/UApp.pas
+++ b/UApp.pas
@@ -49,6 +49,8 @@ type
     FLineFilters: TLineFilters;
     FCurrentLineFilter: TLineFilter;
     FCommandMatcher: TRegExpr;
+    FCommandFileName: String;
+    FLogFileName: String;
     procedure DoRun; override;
     procedure ProcessCommand(ACommand, AParams: String);
     procedure WriteContent(AContent: String; AFilters: TFilterList;
@@ -87,10 +89,25 @@ var
   lineFilter: TLineFilter;
   line: String;
 begin
-  AssignFile(commandFile, ParamStr(1));
+  if HasOption('h', 'help') or not HasOption('c', 'commandfile') then
+  begin
+    WriteHelp;
+    Terminate;
+    Exit;
+  end;
+
+  FCommandFileName := GetOptionValue('c', 'commandfile');
+
+  if not FileExists(FCommandFileName) then
+  begin
+    Writeln('Commandfile not found: ', FCommandFileName);
+    ExitCode := 1;
+    Terminate;
+    Exit;
+  end;
+
+  AssignFile(commandFile, FCommandFileName);
   Reset(commandFile);
-  AssignFile(logFile, ParamStr(2));
-  Reset(logFile);
 
   // Parse command file first
   while not EOF(commandFile) do
@@ -100,6 +117,19 @@ begin
       ProcessCommand(FCommandMatcher.Match[1], FCommandMatcher.Match[3]);
   end;
 
+  CloseFile(commandFile);
+
+  if not FileExists(FLogFileName) then
+  begin
+    Writeln('Logfile not found: ', FLogFileName);
+    ExitCode := 1;
+    Terminate;
+    Exit;
+  end;
+
+  AssignFile(logFile, FLogFileName);
+  Reset(logFile);
+
   // Filter log
   while not EOF(logFile) do
   begin
@@ -111,7 +141,6 @@ begin
     end;
   end;
 
-  CloseFile(commandFile); //TODO: narrow scope!
   CloseFile(logFile);
 
   Terminate;
@@ -132,6 +161,10 @@ begin
         highlightFilter := THighlightFilter.Create(AParams);
         FCurrentLineFilter.Filters.Add(highlightFilter);
       end;
+    'file':
+      begin
+        FLogFileName := AParams;
+      end;
   end;
 end;
 
@@ -235,7 +268,15 @@ end;
 
 procedure TLogFilterApplication.WriteHelp;
 begin
-
+  Writeln('Usage: ', ExtractFileName(ExeName), ' [options]');
+  Writeln;
+  Writeln('Options:');
+  Writeln('  -c --commandfile=<filename>');
+  Writeln('    specifies the filename with filter commands');
+  Writeln('  -f --logfile=<filename>');
+  Writeln('    specifies the logfile to be parsed');
+  Writeln('  -h --help');
+  Writeln('    show this help screen');
 end;
 
 end.