diff --git a/Source/cmAddDependenciesCommand.cxx b/Source/cmAddDependenciesCommand.cxx
index a77140d..652d8d5 100644
--- a/Source/cmAddDependenciesCommand.cxx
+++ b/Source/cmAddDependenciesCommand.cxx
@@ -30,7 +30,15 @@ bool cmAddDependenciesCommand
     ++s; // skip over target_name
     for (; s != args.end(); ++s)
       {
-      target->AddUtility(s->c_str());
+      if (this->Makefile->FindTargetToUse(s->c_str()))
+        target->AddUtility(s->c_str());
+      else
+        {
+        std::string error = "Adding dependency to non-existent target: ";
+        error += *s;
+        this->SetError(error.c_str());
+        return false;
+        }
       }
     }
   else

diff --git a/Source/cmAddDependenciesCommand.cxx b/Source/cmAddDependenciesCommand.cxx
index a77140d..9045838 100644
--- a/Source/cmAddDependenciesCommand.cxx
+++ b/Source/cmAddDependenciesCommand.cxx
@@ -16,21 +16,49 @@
 // cmDependenciesCommand
 bool cmAddDependenciesCommand
 ::InitialPass(std::vector<std::string> const& args, cmExecutionStatus &)
-{
+  {
   if(args.size() < 2 )
     {
     this->SetError("called with incorrect number of arguments");
     return false;
     }
 
+  cmOStringStream e;
   std::string target_name = args[0];
   if(cmTarget* target = this->Makefile->FindTargetToUse(target_name.c_str()))
     {
     std::vector<std::string>::const_iterator s = args.begin();
+    std::string error;
     ++s; // skip over target_name
     for (; s != args.end(); ++s)
       {
-      target->AddUtility(s->c_str());
+      if (this->Makefile->FindTargetToUse(s->c_str()))
+        target->AddUtility(s->c_str());
+      else
+        switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0019))
+          {
+        case cmPolicies::WARN:
+        case cmPolicies::OLD:          // TBD OLD behavior does not warn?
+          // Print the warning.
+          e << "\n"
+              << "CMake does not support this but it used to work accidentally "
+              << "and is being allowed for compatibility."
+              << "\n" << this->Makefile->GetPolicies()->
+              GetPolicyWarning(cmPolicies::CMP0019);
+          target->AddUtility(s->c_str());
+          break;
+        case cmPolicies::REQUIRED_IF_USED:
+        case cmPolicies::REQUIRED_ALWAYS:
+        case cmPolicies::NEW:  // NEW behavior prints the error.
+          e << "\n" << this->Makefile->GetPolicies()->
+            GetRequiredPolicyError(cmPolicies::CMP0019);
+          error = "Adding dependency to non-existent target: ";
+          error += *s;
+          this->SetError(error.c_str());
+          return false;
+        default:
+          break;
+          }
       }
     }
   else
@@ -42,5 +70,5 @@ bool cmAddDependenciesCommand
     }
 
   return true;
-}
+  }
 
diff --git a/Source/cmPolicies.cxx b/Source/cmPolicies.cxx
index 79af4d7..88486b9 100644
--- a/Source/cmPolicies.cxx
+++ b/Source/cmPolicies.cxx
@@ -491,6 +491,12 @@ cmPolicies::cmPolicies()
     "CMAKE_SHARED_LIBRARY_<Lang>_FLAGS whether it is modified or not and "
     "honor the POSITION_INDEPENDENT_CODE target property.",
     2,8,9,0, cmPolicies::WARN);
+
+    this->DefinePolicy(
+    CMP0019, "CMP0019",
+    "add_dependencies() Dependent targets must all exist.",
+    "The NEW behavior for this policy is to warn",
+    2,8,9,0, cmPolicies::WARN);
 }
 
 cmPolicies::~cmPolicies()
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 6932565..e4edabf 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -68,6 +68,7 @@ public:
     CMP0018, ///< Ignore language flags for shared libs, and adhere to
     /// POSITION_INDEPENDENT_CODE property and *_COMPILE_OPTIONS_PI{E,C}
     /// instead.
+    CMP0019, ///< Dependent target must exist
 
     /** \brief Always the last entry.
      *

diff --git a/Source/cmComputeTargetDepends.cxx b/Source/cmComputeTargetDepends.cxx
index ab77c6b..5041746 100644
--- a/Source/cmComputeTargetDepends.cxx
+++ b/Source/cmComputeTargetDepends.cxx
@@ -248,6 +248,43 @@ void cmComputeTargetDepends::AddTargetDepend(int depender_index,
   cmTarget* dependee =
     depender->GetMakefile()->FindTargetToUse(dependee_name);
 
+  if (!dependee && !linking &&
+      (depender->GetType() != cmTarget::GLOBAL_TARGET))
+    {
+    cmOStringStream e;
+    switch (depender->GetMakefile()->GetPolicyStatus(cmPolicies::CMP0019))
+      {
+      case cmPolicies::WARN:    // TBD Print the warning.
+        e << "\n"
+          << "CMake does not support this but it used to work accidentally "
+          << "and is being allowed for compatibility."
+          << "\n" << depender->GetMakefile()->GetPolicies()->
+            GetPolicyWarning(cmPolicies::CMP0019)
+          << "\n";
+        e << depender->GetName()
+          << ": Adding dependency to non-existent target: "
+          << dependee_name
+          << "\n";
+        cmSystemTools::Message(e.str().c_str());
+        break;
+      case cmPolicies::NEW:     // NEW behavior prints the error.
+        e << "\n" << depender->GetMakefile()->GetPolicies()->
+            GetPolicyWarning(cmPolicies::CMP0019)
+          << "\n";
+        e << depender->GetName()
+          << ": Adding dependency to non-existent target: "
+          << dependee_name
+          << "\n";
+        cmSystemTools::Error(e.str().c_str());  //FIXME: this does not break the generation!
+        return;
+      case cmPolicies::REQUIRED_IF_USED:    // TBD
+      case cmPolicies::REQUIRED_ALWAYS:     // TBD
+      case cmPolicies::OLD:     // OLD behavior does not warn!
+      default:
+        break;
+      }
+    }
+
   // Skip targets that will not really be linked.  This is probably a
   // name conflict between an external library and an executable
   // within the project.
diff --git a/Source/cmPolicies.cxx b/Source/cmPolicies.cxx
index 79af4d7..88486b9 100644
--- a/Source/cmPolicies.cxx
+++ b/Source/cmPolicies.cxx
@@ -491,6 +491,12 @@ cmPolicies::cmPolicies()
     "CMAKE_SHARED_LIBRARY_<Lang>_FLAGS whether it is modified or not and "
     "honor the POSITION_INDEPENDENT_CODE target property.",
     2,8,9,0, cmPolicies::WARN);
+
+    this->DefinePolicy(
+    CMP0019, "CMP0019",
+    "add_dependencies() Dependent targets must all exist.",
+    "The NEW behavior for this policy is to warn",
+    2,8,9,0, cmPolicies::WARN);
 }
 
 cmPolicies::~cmPolicies()
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 6932565..e4edabf 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -68,6 +68,7 @@ public:
     CMP0018, ///< Ignore language flags for shared libs, and adhere to
     /// POSITION_INDEPENDENT_CODE property and *_COMPILE_OPTIONS_PI{E,C}
     /// instead.
+    CMP0019, ///< Dependent target must exist
 
     /** \brief Always the last entry.
      *

diff --git a/Source/cmComputeTargetDepends.cxx b/Source/cmComputeTargetDepends.cxx
index ab77c6b..fb5022f 100644
--- a/Source/cmComputeTargetDepends.cxx
+++ b/Source/cmComputeTargetDepends.cxx
@@ -248,6 +248,40 @@ void cmComputeTargetDepends::AddTargetDepend(int depender_index,
   cmTarget* dependee =
     depender->GetMakefile()->FindTargetToUse(dependee_name);
 
+  if (!dependee && !linking &&
+      (depender->GetType() != cmTarget::GLOBAL_TARGET))
+    {
+    cmOStringStream e;
+    switch (depender->GetMakefile()->GetPolicyStatus(cmPolicies::CMP0019))
+      {
+      case cmPolicies::WARN:    // Print the warning message only.
+        e << "\n"
+          << "CMake does not support this but it used to work accidentally "
+          << "and is being allowed for compatibility."
+          << "\n" << depender->GetMakefile()->GetPolicies()->
+            GetPolicyWarning(cmPolicies::CMP0019)
+          << "\n";
+        e << depender->GetName()
+          << ": Adding dependency to non-existent target: "
+          << dependee_name
+          << "\n";
+        cmSystemTools::Message(e.str().c_str());
+        break;
+      case cmPolicies::NEW:     // New behavior prints the error.
+        e << depender->GetName()
+          << ": Adding dependency to non-existent target: "
+          << dependee_name
+          << "\n";
+        cmSystemTools::Error(e.str().c_str());
+        return;
+      case cmPolicies::REQUIRED_IF_USED:    // TBD
+      case cmPolicies::REQUIRED_ALWAYS:     // TBD
+      case cmPolicies::OLD:     // Old behavior does not warn!
+      default:
+        break;
+      }
+    }
+
   // Skip targets that will not really be linked.  This is probably a
   // name conflict between an external library and an executable
   // within the project.
diff --git a/Source/cmPolicies.cxx b/Source/cmPolicies.cxx
index 79af4d7..6615e22 100644
--- a/Source/cmPolicies.cxx
+++ b/Source/cmPolicies.cxx
@@ -491,6 +491,16 @@ cmPolicies::cmPolicies()
     "CMAKE_SHARED_LIBRARY_<Lang>_FLAGS whether it is modified or not and "
     "honor the POSITION_INDEPENDENT_CODE target property.",
     2,8,9,0, cmPolicies::WARN);
+
+    this->DefinePolicy(
+    CMP0019, "CMP0019",
+    "add_dependencies(target-name depend-target1 depend-target2 ...) "
+    "Dependent targets must all exist.  ",
+    "In CMake 2.8.9 and above this policy determines whether or not "
+    "the case is an error.  "
+    "The OLD behavior for this policy is to silently ignore the problem.  "
+    "The NEW behavior for this policy is to report an error.",
+    2,8,9,0, cmPolicies::WARN);
 }
 
 cmPolicies::~cmPolicies()
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 6932565..e4edabf 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -68,6 +68,7 @@ public:
     CMP0018, ///< Ignore language flags for shared libs, and adhere to
     /// POSITION_INDEPENDENT_CODE property and *_COMPILE_OPTIONS_PI{E,C}
     /// instead.
+    CMP0019, ///< Dependent target must exist
 
     /** \brief Always the last entry.
      *