diff --git a/src/quickbook.cpp b/src/quickbook.cpp
index 31c3005..14b7a19 100644
--- a/src/quickbook.cpp
+++ b/src/quickbook.cpp
@@ -118,12 +118,14 @@ namespace quickbook
             indent(-1),
             linewidth(-1),
             pretty_print(true),
+            strict_mode(false),
             deps_out_flags(quickbook::dependency_tracker::default_)
         {}
 
         int indent;
         int linewidth;
         bool pretty_print;
+        bool strict_mode;
         fs::path deps_out;
         quickbook::dependency_tracker::flags deps_out_flags;
         fs::path locations_out;
@@ -143,6 +145,7 @@ namespace quickbook
 
         try {
             quickbook::state state(filein_, options_.xinclude_base, buffer, output);
+            state.strict_mode = options_.strict_mode;
             set_macros(state);
 
             if (state.error_count == 0) {
@@ -279,6 +282,7 @@ main(int argc, char* argv[])
             ("help", "produce help message")
             ("version", "print version string")
             ("no-pretty-print", "disable XML pretty printing")
+            ("strict", "strict mode")
             ("no-self-linked-headers", "stop headers linking to themselves")
             ("indent", PO_VALUE<int>(), "indent spaces")
             ("linewidth", PO_VALUE<int>(), "line width")
@@ -383,6 +387,8 @@ main(int argc, char* argv[])
         if (vm.count("no-pretty-print"))
             parse_document_options.pretty_print = false;
 
+        parse_document_options.strict_mode = !!vm.count("strict");
+
         quickbook::self_linked_headers = !vm.count("no-self-linked-headers");
 
         if (vm.count("indent"))
diff --git a/src/state.cpp b/src/state.cpp
index be14604..790933a 100644
--- a/src/state.cpp
+++ b/src/state.cpp
@@ -46,6 +46,7 @@ namespace quickbook
         , callout_depth(0)
         , dependencies()
         , explicit_list(false)
+        , strict_mode(false)
 
         , imported(false)
         , macro()
diff --git a/src/state.hpp b/src/state.hpp
index e427190..c4efb73 100644
--- a/src/state.hpp
+++ b/src/state.hpp
@@ -56,6 +56,7 @@ namespace quickbook
         int                     callout_depth;      // they don't nest.
         dependency_tracker      dependencies;
         bool                    explicit_list;      // set when using a list
+        bool                    strict_mode;
 
     // state saved for files and templates.
         bool                    imported;
diff --git a/test/src/text_diff.cpp b/test/src/text_diff.cpp
index bcac672..1617f9c 100644
--- a/test/src/text_diff.cpp
+++ b/test/src/text_diff.cpp
@@ -9,6 +9,8 @@
 #include <fstream>
 #include <iostream>
 #include <iterator>
+#include <cstring>
+#include <vector>
 
 #include <boost/spirit/include/classic_scanner.hpp>
 #include <boost/spirit/include/classic_primitives.hpp>
@@ -20,17 +22,37 @@ typedef spirit::scanner<iterator> scanner;
 
 int main(int argc, char * argv[])
 {
-    if (argc != 3)
+    std::vector<char*> args;
+    bool usage_error = false;
+
+    for (int i = 1; i < argc; ++i) {
+        if (std::strncmp(argv[i], "--", 2) == 0) {
+            if (strcmp(argv[i], "--strict") == 0) {
+                // Ignore --strict because the build file accidentally
+                // uses it. Why yes, this is a horrible hack.
+            } else {
+                std::cerr << "ERROR: Invalid flag: " << argv[i] << std::endl;
+                usage_error = true;
+            }
+        } else {
+            args.push_back(argv[i]);
+        }
+    }
+
+    if (!usage_error && args.size() != 2)
     {
         std::cerr << "ERROR: Wrong number of arguments." << std::endl;
-        std::cout << "Usage:\n\t" << argv[0] << " file1 file2" << std::endl;
+        usage_error = true;
+    }
 
+    if (usage_error) {
+        std::cout << "Usage:\n\t" << argv[0] << " file1 file2" << std::endl;
         return 1;
     }
 
     std::ifstream
-        file1(argv[1], std::ios_base::binary | std::ios_base::in),
-        file2(argv[2], std::ios_base::binary | std::ios_base::in);
+        file1(args[0], std::ios_base::binary | std::ios_base::in),
+        file2(args[1], std::ios_base::binary | std::ios_base::in);
 
     if (!file1 || !file2)
     {