diff --git a/src/sketch.h b/src/sketch.h
index e8d17a6..abf35fc 100644
--- a/src/sketch.h
+++ b/src/sketch.h
@@ -106,6 +106,7 @@ public:
     bool        visible;
     bool        suppress;
     bool        relaxConstraints;
+    bool        allowRedundant;
     bool        allDimsReference;
     double      scale;
 
@@ -194,6 +195,7 @@ public:
 
     static void AddParam(ParamList *param, hParam hp, double v);
     void Generate(EntityList *entity, ParamList *param);
+    bool IsSolvedOkay();
     void TransformImportedBy(Vector t, Quaternion q);
     // When a request generates entities from entities, and the source
     // entities may have come from multiple requests, it's necessary to
diff --git a/src/system.cpp b/src/system.cpp
index ad2ea48..74d1cfe 100644
--- a/src/system.cpp
+++ b/src/system.cpp
@@ -460,9 +460,12 @@ int System::Solve(Group *g, int *dof, List<hConstraint> *bad,
         goto didnt_converge;
     }
 
-    if(!TestRank()) {
-        if(andFindBad) FindWhichToRemoveToFixJacobian(g, bad);
-        return System::REDUNDANT_OKAY;
+    rankOk = TestRank();
+    if(!rankOk) {
+        if(!g->allowRedundant) {
+            if(andFindBad) FindWhichToRemoveToFixJacobian(g, bad);
+            return System::REDUNDANT_OKAY;
+        }
     }
 
     // This is not the full Jacobian, but any substitutions or single-eq
@@ -506,7 +509,7 @@ int System::Solve(Group *g, int *dof, List<hConstraint> *bad,
         pp->known = true;
         pp->free = p->free;
     }
-    return System::SOLVED_OKAY;
+    return rankOk ? System::SOLVED_OKAY : System::REDUNDANT_OKAY;
 
 didnt_converge:
     SK.constraint.ClearTags();
diff --git a/src/ui.h b/src/ui.h
index 45e3c30..467592e 100644
--- a/src/ui.h
+++ b/src/ui.h
@@ -271,6 +271,8 @@ public:
     static void ScreenChangeCanvasSize(int link, uint32_t v);
     static void ScreenChangeShadedTriangles(int link, uint32_t v);
 
+    static void ScreenAllowRedundant(int link, uint32_t v);
+
     static void ScreenStepDimSteps(int link, uint32_t v);
     static void ScreenStepDimFinish(int link, uint32_t v);
     static void ScreenStepDimGo(int link, uint32_t v);