diff --git a/lib/binary.js b/lib/binary.js
index 3cb41757..b3d872c2 100644
--- a/lib/binary.js
+++ b/lib/binary.js
@@ -274,6 +274,32 @@ class Binary {
   toString(format) {
     return this.buffer != null ? this.buffer.slice(0, this.position).toString(format) : '';
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    const base64String = Buffer.isBuffer(this.buffer)
+      ? this.buffer.toString('base64')
+      : Buffer.from(this.buffer).toString('base64');
+
+    const subType = Number(this.sub_type).toString(16);
+    return {
+      $binary: {
+        base64: base64String,
+        subType: subType.length === 1 ? '0' + subType : subType
+      }
+    };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    const type = doc.$binary.subType ? parseInt(doc.$binary.subType, 16) : 0;
+    const data = new Buffer(doc.$binary.base64, 'base64');
+    return new Binary(data, type);
+  }
 }
 
 /**
diff --git a/lib/code.js b/lib/code.js
index 1db9089b..21a9cc08 100644
--- a/lib/code.js
+++ b/lib/code.js
@@ -22,6 +22,24 @@ class Code {
   toJSON() {
     return { scope: this.scope, code: this.code };
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    if (this.scope) {
+      return { $code: this.code, $scope: this.scope };
+    }
+
+    return { $code: this.code };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    return new Code(doc.$code, doc.$scope);
+  }
 }
 
 Object.defineProperty(Code.prototype, '_bsontype', { value: 'Code' });
diff --git a/lib/db_ref.js b/lib/db_ref.js
index f1d5f716..77633491 100644
--- a/lib/db_ref.js
+++ b/lib/db_ref.js
@@ -42,6 +42,29 @@ class DBRef {
     if (this.db != null) o.$db = this.db;
     return o;
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    let o = {
+      $ref: this.collection,
+      $id: this.oid
+    };
+
+    if (this.db) o.$db = this.db;
+    o = Object.assign(o, this.fields);
+    return o;
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    var copy = Object.assign({}, doc);
+    ['$ref', '$id', '$db'].forEach(k => delete copy[k]);
+    return new DBRef(doc.$ref, doc.$id, doc.$db, copy);
+  }
 }
 
 Object.defineProperty(DBRef.prototype, '_bsontype', { value: 'DBRef' });
diff --git a/lib/decimal128.js b/lib/decimal128.js
index 3e2a5716..d4a285c6 100644
--- a/lib/decimal128.js
+++ b/lib/decimal128.js
@@ -788,5 +788,19 @@ Decimal128.prototype.toJSON = function() {
   return { $numberDecimal: this.toString() };
 };
 
+/**
+ * @ignore
+ */
+Decimal128.prototype.toExtendedJSON = function() {
+  return { $numberDecimal: this.toString() };
+};
+
+/**
+ * @ignore
+ */
+Decimal128.fromExtendedJSON = function(doc) {
+  return Decimal128.fromString(doc.$numberDecimal);
+};
+
 Object.defineProperty(Decimal128.prototype, '_bsontype', { value: 'Decimal128' });
 module.exports = Decimal128;
diff --git a/lib/double.js b/lib/double.js
index ae28390d..03f9e405 100644
--- a/lib/double.js
+++ b/lib/double.js
@@ -29,6 +29,23 @@ class Double {
   toJSON() {
     return this.value;
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON(options) {
+    if (options && options.relaxed && isFinite(this.value)) return this.value;
+    return { $numberDouble: this.value.toString() };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc, options) {
+    return options && options.relaxed
+      ? parseFloat(doc.$numberDouble)
+      : new Double(parseFloat(doc.$numberDouble));
+  }
 }
 
 Object.defineProperty(Double.prototype, '_bsontype', { value: 'Double' });
diff --git a/lib/int_32.js b/lib/int_32.js
index 1f064691..5ef5f95a 100644
--- a/lib/int_32.js
+++ b/lib/int_32.js
@@ -29,6 +29,21 @@ class Int32 {
   toJSON() {
     return this.value;
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON(options) {
+    if (options && options.relaxed) return this.value;
+    return { $numberInt: this.value.toString() };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc, options) {
+    return options && options.relaxed ? parseInt(doc.$numberInt, 10) : new Int32(doc.$numberInt);
+  }
 }
 
 Object.defineProperty(Int32.prototype, '_bsontype', { value: 'Int32' });
diff --git a/lib/long.js b/lib/long.js
index dc5a5826..c9f9f833 100644
--- a/lib/long.js
+++ b/lib/long.js
@@ -1,5 +1,21 @@
 'use strict';
 const Long = require('long');
 
+/**
+ * @ignore
+ */
+Long.prototype.toExtendedJSON = function(options) {
+  if (options && options.relaxed) return this.toNumber();
+  return { $numberLong: this.toString() };
+};
+
+/**
+ * @ignore
+ */
+Long.fromExtendedJSON = function(doc, options) {
+  const result = Long.fromString(doc.$numberLong);
+  return options && options.relaxed ? result.toNumber() : result;
+};
+
 Object.defineProperty(Long.prototype, '_bsontype', { value: 'Long' });
 module.exports = Long;
diff --git a/lib/max_key.js b/lib/max_key.js
index 0b97a41e..b308c77a 100644
--- a/lib/max_key.js
+++ b/lib/max_key.js
@@ -9,6 +9,20 @@ class MaxKey {
    * @return {MaxKey} A MaxKey instance
    */
   constructor() {}
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    return { $maxKey: 1 };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON() {
+    return new MaxKey();
+  }
 }
 
 Object.defineProperty(MaxKey.prototype, '_bsontype', { value: 'MaxKey' });
diff --git a/lib/min_key.js b/lib/min_key.js
index f4c59f7e..add6bd12 100644
--- a/lib/min_key.js
+++ b/lib/min_key.js
@@ -9,6 +9,20 @@ class MinKey {
    * @return {MinKey} A MinKey instance
    */
   constructor() {}
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    return { $minKey: 1 };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON() {
+    return new MinKey();
+  }
 }
 
 Object.defineProperty(MinKey.prototype, '_bsontype', { value: 'MinKey' });
diff --git a/lib/objectid.js b/lib/objectid.js
index 4d28c9e8..e83d09ae 100644
--- a/lib/objectid.js
+++ b/lib/objectid.js
@@ -351,6 +351,21 @@ class ObjectId {
 
     return false;
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    if (this.toHexString) return { $oid: this.toHexString() };
+    return { $oid: this.toString('hex') };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    return new ObjectId(doc.$oid);
+  }
 }
 
 /**
diff --git a/lib/regexp.js b/lib/regexp.js
index ab6ff36a..ac8c2355 100644
--- a/lib/regexp.js
+++ b/lib/regexp.js
@@ -38,6 +38,26 @@ class BSONRegExp {
       }
     }
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    return { $regularExpression: { pattern: this.pattern, options: this.options } };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    return new BSONRegExp(
+      doc.$regularExpression.pattern,
+      doc.$regularExpression.options
+        .split('')
+        .sort()
+        .join('')
+    );
+  }
 }
 
 Object.defineProperty(BSONRegExp.prototype, '_bsontype', { value: 'BSONRegExp' });
diff --git a/lib/symbol.js b/lib/symbol.js
index 060d3d0e..8bd975e6 100644
--- a/lib/symbol.js
+++ b/lib/symbol.js
@@ -42,6 +42,20 @@ class Symbol {
   toJSON() {
     return this.value;
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    return { $symbol: this.value };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    return new Symbol(doc.$symbol);
+  }
 }
 
 Object.defineProperty(Symbol.prototype, '_bsontype', { value: 'Symbol' });
diff --git a/lib/timestamp.js b/lib/timestamp.js
index 6d88a2ad..9b5249e1 100644
--- a/lib/timestamp.js
+++ b/lib/timestamp.js
@@ -74,6 +74,20 @@ class Timestamp extends Long {
   static fromString(str, opt_radix) {
     return new Timestamp(Long.fromString(str, opt_radix));
   }
+
+  /**
+   * @ignore
+   */
+  toExtendedJSON() {
+    return { $timestamp: { t: this.high, i: this.low } };
+  }
+
+  /**
+   * @ignore
+   */
+  static fromExtendedJSON(doc) {
+    return new Timestamp(doc.$timestamp.i, doc.$timestamp.t);
+  }
 }
 
 Object.defineProperty(Timestamp.prototype, '_bsontype', { value: 'Timestamp' });