diff --git a/README.adoc b/README.adoc
index 6fe7e78..022c24b 100644
--- a/README.adoc
+++ b/README.adoc
@@ -61,6 +61,21 @@ pubid.to_s
 => "ISO/WD 1234"
 ----
 
+==== "PreCD" stage
+
+For "PreCD" stage we’re using a special stage called "29" that is not in the International Harmonized Codes.
+
+[source,ruby]
+----
+pubid = Pubid::Iso::Identifier.create(publisher: "ISO", stage: :PreCD, number: 123)
+pubid.to_s
+
+=> "ISO/PreCD 123"
+
+subject.stage.harmonized_code.stages
+=> ["29.00", "29.20", "29.60", "29.92", "29.98", "29.99"]
+----
+
 === With part number
 
 [source,ruby]
diff --git a/lib/pubid/iso/parser.rb b/lib/pubid/iso/parser.rb
index 1ca727b..7813a2e 100644
--- a/lib/pubid/iso/parser.rb
+++ b/lib/pubid/iso/parser.rb
@@ -49,7 +49,8 @@ class Parser < Pubid::Core::Parser
     end
 
     rule(:stage) do
-      array_to_str(Pubid::Iso::Renderer::Base::TRANSLATION[:russian][:stage].values) | array_to_str(STAGES)
+      array_to_str(Pubid::Iso::Renderer::Base::TRANSLATION[:russian][:stage].values) | array_to_str(STAGES) |
+        (str("preCD") | str("PreCD"))
     end
 
     rule(:typed_stage) do
diff --git a/lib/pubid/iso/transformer.rb b/lib/pubid/iso/transformer.rb
index abc86d7..7f920f4 100644
--- a/lib/pubid/iso/transformer.rb
+++ b/lib/pubid/iso/transformer.rb
@@ -136,6 +136,8 @@ def self.convert_stage(code)
         { stage: "CD", type: "TR" }
       when "PDTS"
         { stage: "CD", type: "TS" }
+      when "preCD"
+        { stage: "PreCD" }
       else
         { stage: code }
       end
diff --git a/spec/pubid_iso/identifier/create_new_identifier_spec.rb b/spec/pubid_iso/identifier/create_new_identifier_spec.rb
index 2522a0f..14426c6 100644
--- a/spec/pubid_iso/identifier/create_new_identifier_spec.rb
+++ b/spec/pubid_iso/identifier/create_new_identifier_spec.rb
@@ -140,6 +140,14 @@ module Pubid::Iso
             end
           end
         end
+
+        context "stage is PreCD" do
+          let(:stage) { "PreCD" }
+
+          it "renders separate stage for PubID" do
+            expect(subject.to_s).to eq("ISO/PreCD #{number}")
+          end
+        end
       end
 
       context "when TS type" do
diff --git a/spec/pubid_iso/identifier_parsing_spec.rb b/spec/pubid_iso/identifier_parsing_spec.rb
index eaebab0..4d41643 100644
--- a/spec/pubid_iso/identifier_parsing_spec.rb
+++ b/spec/pubid_iso/identifier_parsing_spec.rb
@@ -1032,5 +1032,19 @@ module Pubid::Iso
 
       it_behaves_like "converts pubid to pubid with prf"
     end
+
+    context "ISO/IEC preCD 29135" do
+      let(:original) { "ISO/IEC preCD 29135" }
+      let(:pubid) { "ISO/IEC PreCD 29135" }
+
+      it_behaves_like "converts pubid to pubid"
+    end
+
+    context "ISO/PreCD3 17301-1" do
+      let(:original) { "ISO/PreCD3 17301-1" }
+      let(:pubid) { "ISO/PreCD 17301-1.3" }
+
+      it_behaves_like "converts pubid to pubid"
+    end
   end
 end
diff --git a/stages.yaml b/stages.yaml
index 46350d5..f46078d 100644
--- a/stages.yaml
+++ b/stages.yaml
@@ -3,6 +3,7 @@ abbreviations:
   NP: ["10.00", "10.20", "10.60", "10.98", "10.92"]
   AWI: ["20.00", "10.99"]
   WD: ["20.20", "20.60", "20.98", "20.99"]
+  PreCD: ["29.00", "29.20", "29.60", "29.92", "29.98", "29.99"]
   CD: ["30.00", "30.20", "30.60", "30.92", "30.98", "30.99"]
   FCD: ["40.00", "40.20", "40.60", "40.92", "40.98", "40.99"]
   PRF: ["50.00", "50.20", "50.60", "50.92", "50.98", "50.99"]
@@ -32,6 +33,12 @@ codes_description:
   "20.60": Close of comment period
   "20.98": Project deleted
   "20.99": WD approved for registration as CD
+  "29.00": Committee draft (CD) registered
+  "29.20": CD study/ballot initiated
+  "29.60": Close of voting/ comment period
+  "29.92": CD referred back to Working Group
+  "29.98": Project deleted
+  "29.99": CD approved for registration as DIS
   "30.00": Committee draft (CD) registered
   "30.20": CD study/ballot initiated
   "30.60": Close of voting/ comment period
@@ -84,9 +91,9 @@ substage_codes:
   proceed: "99"
 
 draft_codes: ["00.00", "00.20", "00.60", "00.99", "10.00", "10.20", "10.60", "10.92",
-  "10.99", "20.00", "20.20", "20.60", "20.99", "30.00",
-  "30.20", "30.60", "30.92", "30.99", "40.00", "40.20", "40.60", "40.92",
-  "40.93", "40.99", "50.00", "50.20", "50.60", "50.92", "50.99"]
+  "10.99", "20.00", "20.20", "20.60", "20.99", "29.00", "29.20", "29.60", "29.92",
+  "29.99", "30.00", "30.20", "30.60", "30.92", "30.99", "40.00", "40.20", "40.60",
+  "40.92", "40.93", "40.99", "50.00", "50.20", "50.60", "50.92", "50.99"]
 
 canceled_codes: ["00.98", "10.98", "20.98", "30.98", "40.98", "50.98", "95.99"]
 published_codes: ["60.00", "60.60", "90.20", "90.60", "90.92", "90.93", "90.99", "95.20", "95.60", "95.92"]