diff --git a/Makefile b/Makefile
index 67667e14..0042ec5b 100644
--- a/Makefile
+++ b/Makefile
@@ -44,6 +44,7 @@ samples:
 	@PATH=./bin:$$PATH; protoc --jsonschema_out=jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/Proto2Required.proto || echo "No messages found (Proto2Required.proto)"
 	@PATH=./bin:$$PATH; protoc --jsonschema_out=jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/Proto2NestedMessage.proto || echo "No messages found (Proto2NestedMessage.proto)"
 	@PATH=./bin:$$PATH; protoc --jsonschema_out=jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/GoogleValue.proto || echo "No messages found (GoogleValue.proto)"
+	@PATH=./bin:$$PATH; protoc --jsonschema_out=exclude_ignored_fields:jsonschemas -I. --proto_path=${PROTO_PATH} ${PROTO_PATH}/HiddenFields.proto || echo "No messages found (HiddenFields.proto)"
 	@PATH=./bin:$$PATH; protoc --jsonschema_out=enforce_oneof:jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/OneOf.proto || echo "No messages found (OneOf.proto)"
 	@PATH=./bin:$$PATH; protoc --jsonschema_out=all_fields_required:jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/Proto2NestedObject.proto || echo "No messages found (Proto2NestedObject.proto)"
 	@PATH=./bin:$$PATH; protoc -I /usr/include --jsonschema_out=jsonschemas --proto_path=${PROTO_PATH} ${PROTO_PATH}/WellKnown.proto || echo "No messages found (WellKnown.proto)"
diff --git a/README.md b/README.md
index 9d34cd0b..91f3e62f 100644
--- a/README.md
+++ b/README.md
@@ -39,8 +39,9 @@ protoc \ # The protobuf compiler
 |`debug`| Enable debug logging |
 |`disallow_additional_properties`| Disallow additional properties in schema |
 |`disallow_bigints_as_strings`| Disallow big integers as strings |
-|`enforce_oneof` | Interpret Proto "oneOf" clauses |
-|`json_fieldnames` | Use JSON field names only |
+|`enforce_oneof`| Interpret Proto "oneOf" clauses |
+|`exclude_ignored_fields`| Omit fields marked with the custom "ignore" option |
+|`json_fieldnames`| Use JSON field names only |
 |`prefix_schema_files_with_package`| Prefix the output filename with package |
 |`proto_and_json_fieldnames`| Use proto and JSON field names |
 
diff --git a/internal/converter/converter.go b/internal/converter/converter.go
index 87aa899a..e9decf61 100644
--- a/internal/converter/converter.go
+++ b/internal/converter/converter.go
@@ -17,15 +17,17 @@ import (
 )
 
 const (
-	messageDelimiter = "+"
+	ignoredFieldOption = "50505:1"
+	messageDelimiter   = "+"
 )
 
 // Converter is everything you need to convert protos to JSONSchemas:
 type Converter struct {
-	Flags          ConverterFlags
-	logger         *logrus.Logger
-	sourceInfo     *sourceCodeInfo
-	messageTargets []string
+	Flags              ConverterFlags
+	ignoredFieldOption string
+	logger             *logrus.Logger
+	sourceInfo         *sourceCodeInfo
+	messageTargets     []string
 }
 
 // ConverterFlags control the behaviour of the converter:
@@ -35,6 +37,7 @@ type ConverterFlags struct {
 	DisallowAdditionalProperties bool
 	DisallowBigIntsAsStrings     bool
 	EnforceOneOf                 bool
+	ExcludeIgnoredFields         bool
 	PrefixSchemaFilesWithPackage bool
 	UseJSONFieldnamesOnly        bool
 	UseProtoAndJSONFieldNames    bool
@@ -43,7 +46,8 @@ type ConverterFlags struct {
 // New returns a configured *Converter:
 func New(logger *logrus.Logger) *Converter {
 	return &Converter{
-		logger: logger,
+		ignoredFieldOption: ignoredFieldOption,
+		logger:             logger,
 	}
 }
 
@@ -82,6 +86,8 @@ func (c *Converter) parseGeneratorParameters(parameters string) {
 			c.Flags.DisallowBigIntsAsStrings = true
 		case "enforce_oneof":
 			c.Flags.EnforceOneOf = true
+		case "exclude_ignored_fields":
+			c.Flags.ExcludeIgnoredFields = true
 		case "json_fieldnames":
 			c.Flags.UseJSONFieldnamesOnly = true
 		case "prefix_schema_files_with_package":
diff --git a/internal/converter/converter_test.go b/internal/converter/converter_test.go
index 60c579d8..9642521c 100644
--- a/internal/converter/converter_test.go
+++ b/internal/converter/converter_test.go
@@ -268,6 +268,12 @@ func configureSampleProtos() map[string]sampleProto {
 			FilesToGenerate:    []string{"OneOf.proto"},
 			ProtoFileName:      "OneOf.proto",
 		},
+		"HiddenFields": {
+			Flags:              ConverterFlags{ExcludeIgnoredFields: true},
+			ExpectedJSONSchema: []string{testdata.HiddenFields},
+			FilesToGenerate:    []string{"options.proto", "HiddenFields.proto"},
+			ProtoFileName:      "HiddenFields.proto",
+		},
 	}
 }
 
@@ -284,6 +290,7 @@ func mustReadProtoFiles(t *testing.T, includePath string, filenames ...string) *
 	args = append(args, "--descriptor_set_out=/dev/stdout")
 	args = append(args, "--include_source_info")
 	args = append(args, "--include_imports")
+	args = append(args, "-I../../")
 	args = append(args, "--proto_path="+includePath)
 	args = append(args, filenames...)
 	cmd := exec.Command(protocBinary, args...)
diff --git a/internal/converter/testdata/hidden_fields.go b/internal/converter/testdata/hidden_fields.go
new file mode 100644
index 00000000..d283fdc9
--- /dev/null
+++ b/internal/converter/testdata/hidden_fields.go
@@ -0,0 +1,15 @@
+package testdata
+
+const HiddenFields = `{
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "properties": {
+        "visible1": {
+            "type": "string"
+        },
+        "visible2": {
+            "type": "string"
+        }
+    },
+    "additionalProperties": true,
+    "type": "object"
+}`
diff --git a/internal/converter/testdata/proto/HiddenFields.proto b/internal/converter/testdata/proto/HiddenFields.proto
new file mode 100644
index 00000000..8b7abd3b
--- /dev/null
+++ b/internal/converter/testdata/proto/HiddenFields.proto
@@ -0,0 +1,10 @@
+syntax = "proto3";
+package samples;
+import "options.proto";
+
+message HiddenFields {
+    string visible1 = 1 [(protoc.gen.jsonschema.ignore) = false];
+    string visible2 = 2;
+    string hidden1  = 3 [(protoc.gen.jsonschema.ignore) = true];
+    string hidden2  = 4 [deprecated = true, (protoc.gen.jsonschema.ignore) = true];
+}
diff --git a/internal/converter/types.go b/internal/converter/types.go
index 366c0025..b6f9bd52 100644
--- a/internal/converter/types.go
+++ b/internal/converter/types.go
@@ -495,6 +495,13 @@ func (c *Converter) recursiveConvertMessageType(curPkg *ProtoPackage, msg *descr
 
 	c.logger.WithField("message_str", proto.MarshalTextString(msg)).Trace("Converting message")
 	for _, fieldDesc := range msg.GetField() {
+
+		// Look for our custom "ignore" field-option (and hope that nobody else happens to be using our number):
+		if c.Flags.ExcludeIgnoredFields && strings.Contains(fieldDesc.GetOptions().String(), c.ignoredFieldOption) {
+			c.logger.WithField("field_name", fieldDesc.GetName()).WithField("message_name", msg.GetName()).Debug("Omitting ignored field")
+			continue
+		}
+
 		recursedJSONSchemaType, err := c.convertField(curPkg, fieldDesc, msg, duplicatedMessages)
 		if err != nil {
 			c.logger.WithError(err).WithField("field_name", fieldDesc.GetName()).WithField("message_name", msg.GetName()).Error("Failed to convert field")
diff --git a/jsonschemas/Enumception.jsonschema b/jsonschemas/Enumception.jsonschema
index 4e7048db..315afb68 100644
--- a/jsonschemas/Enumception.jsonschema
+++ b/jsonschemas/Enumception.jsonschema
@@ -34,13 +34,14 @@
         },
         "payload": {
             "$ref": "samples.PayloadMessage",
-            "additionalProperties": true
+            "additionalProperties": false
         },
         "payloads": {
             "items": {
                 "$schema": "http://json-schema.org/draft-04/schema#",
                 "$ref": "samples.PayloadMessage"
             },
+            "additionalProperties": false,
             "type": "array"
         },
         "importedEnum": {
diff --git a/jsonschemas/GoogleValue.jsonschema b/jsonschemas/GoogleValue.jsonschema
index 7e164d66..709e6bd5 100644
--- a/jsonschemas/GoogleValue.jsonschema
+++ b/jsonschemas/GoogleValue.jsonschema
@@ -18,7 +18,8 @@
                 {
                     "type": "string"
                 }
-            ]
+            ],
+            "description": "`Value` represents a dynamically typed value which can be either\n null, a number, a string, a boolean, a recursive struct value, or a\n list of values. A producer of value is expected to set one of that\n variants, absence of any variant indicates an error.\n\n The JSON representation for `Value` is JSON value."
         }
     },
     "additionalProperties": true,
diff --git a/jsonschemas/HiddenFields.jsonschema b/jsonschemas/HiddenFields.jsonschema
new file mode 100644
index 00000000..043da7ab
--- /dev/null
+++ b/jsonschemas/HiddenFields.jsonschema
@@ -0,0 +1,13 @@
+{
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "properties": {
+        "visible1": {
+            "type": "string"
+        },
+        "visible2": {
+            "type": "string"
+        }
+    },
+    "additionalProperties": true,
+    "type": "object"
+}
\ No newline at end of file
diff --git a/jsonschemas/NestedMessage.jsonschema b/jsonschemas/NestedMessage.jsonschema
index 88cf76ee..03724ba1 100644
--- a/jsonschemas/NestedMessage.jsonschema
+++ b/jsonschemas/NestedMessage.jsonschema
@@ -43,7 +43,7 @@
                     ]
                 }
             },
-            "additionalProperties": true,
+            "additionalProperties": false,
             "type": "object"
         },
         "description": {
diff --git a/jsonschemas/WellKnown.jsonschema b/jsonschemas/WellKnown.jsonschema
index ac4d47da..940b4bbf 100644
--- a/jsonschemas/WellKnown.jsonschema
+++ b/jsonschemas/WellKnown.jsonschema
@@ -20,13 +20,16 @@
         },
         "list_of_integers": {
             "items": {
-                "type": "integer"
+                "type": "integer",
+                "description": "Wrapper message for `int32`.\n\n The JSON representation for `Int32Value` is JSON number."
             },
             "type": "array"
         },
         "duration": {
-            "additionalProperties": true,
-            "type": "string"
+            "pattern": "^([0-9]+\\.?[0-9]*|\\.[0-9]+)s$",
+            "type": "string",
+            "description": "This is a duration:",
+            "format": "regex"
         }
     },
     "additionalProperties": true,
diff --git a/options.proto b/options.proto
new file mode 100644
index 00000000..95116e53
--- /dev/null
+++ b/options.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+package protoc.gen.jsonschema;
+import "google/protobuf/descriptor.proto";
+
+extend google.protobuf.FieldOptions {
+  optional bool ignore = 50505;
+}