diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 7564fae..2d4122d 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -50,6 +50,8 @@
 - If you were still using the old names, while you are cleaning up, considering enabling
   IMGUI_DISABLE_OBSOLETE_FUNCTIONS in imconfig.h even temporarily to have a pass at finding
   and removing up old API calls, if any remaining.
+- Columns: renamed undocumented/internals ImGuiColumnsFlags_* to ImGuiOldColumnFlags_* in prevision of
+  incoming Tables API. Keep redirection enums (will obsolete). (#125, #513, #913, #1204, #1444, #2142, #2707)
 - Renamed io.ConfigWindowsMemoryCompactTimer to io.ConfigMemoryCompactTimer as the feature will apply
   to other data structures. (#2636)
 
diff --git a/imgui.cpp b/imgui.cpp
index dad7ff7..1743d34 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -371,6 +371,7 @@
  When you are not sure about a old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2020/11/18 (1.80) - renamed undocumented/internals ImGuiColumnsFlags_* to ImGuiOldColumnFlags_* in prevision of incoming Tables API.
  - 2020/11/03 (1.80) - renamed io.ConfigWindowsMemoryCompactTimer to io.ConfigMemoryCompactTimer as the feature will apply to other data structures
  - 2020/10/14 (1.80) - backends: moved all backends files (imgui_impl_XXXX.cpp, imgui_impl_XXXX.h) from examples/ to backends/.
  - 2020/10/12 (1.80) - removed redirecting functions/enums that were marked obsolete in 1.60 (April 2018):
diff --git a/imgui_internal.h b/imgui_internal.h
index afae777..ee2931b 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -117,9 +117,9 @@
 
 // Use your programming IDE "Go to definition" facility on the names of the center columns to find the actual flags/enum lists.
 typedef int ImGuiLayoutType;            // -> enum ImGuiLayoutType_         // Enum: Horizontal or vertical
-typedef int ImGuiColumnsFlags;          // -> enum ImGuiColumnsFlags_       // Flags: BeginColumns()
 typedef int ImGuiItemFlags;             // -> enum ImGuiItemFlags_          // Flags: for PushItemFlag()
 typedef int ImGuiItemStatusFlags;       // -> enum ImGuiItemStatusFlags_    // Flags: for DC.LastItemStatusFlags
+typedef int ImGuiOldColumnFlags;        // -> enum ImGuiOldColumnFlags_     // Flags: for BeginColumns()
 typedef int ImGuiNavHighlightFlags;     // -> enum ImGuiNavHighlightFlags_  // Flags: for RenderNavHighlight()
 typedef int ImGuiNavDirSourceFlags;     // -> enum ImGuiNavDirSourceFlags_  // Flags: for GetNavInputAmount2d()
 typedef int ImGuiNavMoveFlags;          // -> enum ImGuiNavMoveFlags_       // Flags: for navigation requests
@@ -990,22 +990,32 @@
 // [SECTION] Columns support
 //-----------------------------------------------------------------------------
 
-enum ImGuiColumnsFlags_
+// Flags for internal's BeginColumns(). Prefix using BeginTable() nowadays!
+enum ImGuiOldColumnFlags_
 {
-    // Default: 0
-    ImGuiColumnsFlags_None                  = 0,
-    ImGuiColumnsFlags_NoBorder              = 1 << 0,   // Disable column dividers
-    ImGuiColumnsFlags_NoResize              = 1 << 1,   // Disable resizing columns when clicking on the dividers
-    ImGuiColumnsFlags_NoPreserveWidths      = 1 << 2,   // Disable column width preservation when adjusting columns
-    ImGuiColumnsFlags_NoForceWithinWindow   = 1 << 3,   // Disable forcing columns to fit within window
-    ImGuiColumnsFlags_GrowParentContentsSize= 1 << 4    // (WIP) Restore pre-1.51 behavior of extending the parent window contents size but _without affecting the columns width at all_. Will eventually remove.
+    ImGuiOldColumnFlags_None                    = 0,
+    ImGuiOldColumnFlags_NoBorder                = 1 << 0,   // Disable column dividers
+    ImGuiOldColumnFlags_NoResize                = 1 << 1,   // Disable resizing columns when clicking on the dividers
+    ImGuiOldColumnFlags_NoPreserveWidths        = 1 << 2,   // Disable column width preservation when adjusting columns
+    ImGuiOldColumnFlags_NoForceWithinWindow     = 1 << 3,   // Disable forcing columns to fit within window
+    ImGuiOldColumnFlags_GrowParentContentsSize  = 1 << 4    // (WIP) Restore pre-1.51 behavior of extending the parent window contents size but _without affecting the columns width at all_. Will eventually remove.
+
+    // Obsolete names (will be removed)
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    , ImGuiColumnsFlags_None                    = ImGuiOldColumnFlags_None,
+    ImGuiColumnsFlags_NoBorder                  = ImGuiOldColumnFlags_NoBorder,
+    ImGuiColumnsFlags_NoResize                  = ImGuiOldColumnFlags_NoResize,
+    ImGuiColumnsFlags_NoPreserveWidths          = ImGuiOldColumnFlags_NoPreserveWidths,
+    ImGuiColumnsFlags_NoForceWithinWindow       = ImGuiOldColumnFlags_NoForceWithinWindow,
+    ImGuiColumnsFlags_GrowParentContentsSize    = ImGuiOldColumnFlags_GrowParentContentsSize
+#endif
 };
 
 struct ImGuiColumnData
 {
     float               OffsetNorm;         // Column start offset, normalized 0.0 (far left) -> 1.0 (far right)
     float               OffsetNormBeforeResize;
-    ImGuiColumnsFlags   Flags;              // Not exposed
+    ImGuiOldColumnFlags Flags;              // Not exposed
     ImRect              ClipRect;
 
     ImGuiColumnData()   { memset(this, 0, sizeof(*this)); }
@@ -1014,7 +1024,7 @@
 struct ImGuiColumns
 {
     ImGuiID             ID;
-    ImGuiColumnsFlags   Flags;
+    ImGuiOldColumnFlags Flags;
     bool                IsFirstFrame;
     bool                IsBeingResized;
     int                 Current;
@@ -1954,8 +1964,8 @@
 
     // Internal Columns API (this is not exposed because we will encourage transitioning to the Tables API)
     IMGUI_API void          SetWindowClipRectBeforeSetChannel(ImGuiWindow* window, const ImRect& clip_rect);
-    IMGUI_API void          BeginColumns(const char* str_id, int count, ImGuiColumnsFlags flags = 0); // setup number of columns. use an identifier to distinguish multiple column sets. close with EndColumns().
-    IMGUI_API void          EndColumns();                                                             // close columns
+    IMGUI_API void          BeginColumns(const char* str_id, int count, ImGuiOldColumnFlags flags = 0); // setup number of columns. use an identifier to distinguish multiple column sets. close with EndColumns().
+    IMGUI_API void          EndColumns();                                                               // close columns
     IMGUI_API void          PushColumnClipRect(int column_index);
     IMGUI_API void          PushColumnsBackground();
     IMGUI_API void          PopColumnsBackground();
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index b8e7591..4213565 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -7930,7 +7930,7 @@
 
     float x = g.IO.MousePos.x - g.ActiveIdClickOffset.x + COLUMNS_HIT_RECT_HALF_WIDTH - window->Pos.x;
     x = ImMax(x, ImGui::GetColumnOffset(column_index - 1) + g.Style.ColumnsMinSpacing);
-    if ((columns->Flags & ImGuiColumnsFlags_NoPreserveWidths))
+    if ((columns->Flags & ImGuiOldColumnFlags_NoPreserveWidths))
         x = ImMin(x, ImGui::GetColumnOffset(column_index + 1) - g.Style.ColumnsMinSpacing);
 
     return x;
@@ -7989,10 +7989,10 @@
         column_index = columns->Current;
     IM_ASSERT(column_index < columns->Columns.Size);
 
-    const bool preserve_width = !(columns->Flags & ImGuiColumnsFlags_NoPreserveWidths) && (column_index < columns->Count - 1);
+    const bool preserve_width = !(columns->Flags & ImGuiOldColumnFlags_NoPreserveWidths) && (column_index < columns->Count - 1);
     const float width = preserve_width ? GetColumnWidthEx(columns, column_index, columns->IsBeingResized) : 0.0f;
 
-    if (!(columns->Flags & ImGuiColumnsFlags_NoForceWithinWindow))
+    if (!(columns->Flags & ImGuiOldColumnFlags_NoForceWithinWindow))
         offset = ImMin(offset, columns->OffMaxX - g.Style.ColumnsMinSpacing * (columns->Count - column_index));
     columns->Columns[column_index].OffsetNorm = GetColumnNormFromOffset(columns, offset - columns->OffMinX);
 
@@ -8074,7 +8074,7 @@
     return id;
 }
 
-void ImGui::BeginColumns(const char* str_id, int columns_count, ImGuiColumnsFlags flags)
+void ImGui::BeginColumns(const char* str_id, int columns_count, ImGuiOldColumnFlags flags)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = GetCurrentWindow();
@@ -8220,16 +8220,16 @@
         columns->Splitter.Merge(window->DrawList);
     }
 
-    const ImGuiColumnsFlags flags = columns->Flags;
+    const ImGuiOldColumnFlags flags = columns->Flags;
     columns->LineMaxY = ImMax(columns->LineMaxY, window->DC.CursorPos.y);
     window->DC.CursorPos.y = columns->LineMaxY;
-    if (!(flags & ImGuiColumnsFlags_GrowParentContentsSize))
+    if (!(flags & ImGuiOldColumnFlags_GrowParentContentsSize))
         window->DC.CursorMaxPos.x = columns->HostCursorMaxPosX;  // Restore cursor max pos, as columns don't grow parent
 
     // Draw columns borders and handle resize
     // The IsBeingResized flag ensure we preserve pre-resize columns width so back-and-forth are not lossy
     bool is_being_resized = false;
-    if (!(flags & ImGuiColumnsFlags_NoBorder) && !window->SkipItems)
+    if (!(flags & ImGuiOldColumnFlags_NoBorder) && !window->SkipItems)
     {
         // We clip Y boundaries CPU side because very long triangles are mishandled by some GPU drivers.
         const float y1 = ImMax(columns->HostCursorPosY, window->ClipRect.Min.y);
@@ -8247,12 +8247,12 @@
                 continue;
 
             bool hovered = false, held = false;
-            if (!(flags & ImGuiColumnsFlags_NoResize))
+            if (!(flags & ImGuiOldColumnFlags_NoResize))
             {
                 ButtonBehavior(column_hit_rect, column_id, &hovered, &held);
                 if (hovered || held)
                     g.MouseCursor = ImGuiMouseCursor_ResizeEW;
-                if (held && !(column->Flags & ImGuiColumnsFlags_NoResize))
+                if (held && !(column->Flags & ImGuiOldColumnFlags_NoResize))
                     dragging_column = n;
             }
 
@@ -8282,14 +8282,13 @@
     window->DC.CursorPos.x = IM_FLOOR(window->Pos.x + window->DC.Indent.x + window->DC.ColumnsOffset.x);
 }
 
-// [2018-03: This is currently the only public API, while we are working on making BeginColumns/EndColumns user-facing]
 void ImGui::Columns(int columns_count, const char* id, bool border)
 {
     ImGuiWindow* window = GetCurrentWindow();
     IM_ASSERT(columns_count >= 1);
 
-    ImGuiColumnsFlags flags = (border ? 0 : ImGuiColumnsFlags_NoBorder);
-    //flags |= ImGuiColumnsFlags_NoPreserveWidths; // NB: Legacy behavior
+    ImGuiOldColumnFlags flags = (border ? 0 : ImGuiOldColumnFlags_NoBorder);
+    //flags |= ImGuiOldColumnFlags_NoPreserveWidths; // NB: Legacy behavior
     ImGuiColumns* columns = window->DC.CurrentColumns;
     if (columns != NULL && columns->Count == columns_count && columns->Flags == flags)
         return;