diff --git a/uppsrc/Core/Color.cpp b/uppsrc/Core/Color.cpp
index 1ae4a69f1..c0cd439b2 100644
--- a/uppsrc/Core/Color.cpp
+++ b/uppsrc/Core/Color.cpp
@@ -88,6 +88,15 @@ Color::Color(RGBA rgba)
 	}
 }
 
+void Color::Jsonize(JsonIO& jio)
+{
+	int r = GetR();
+	int g = GetG();
+	int b = GetB();
+	jio("red", r)("green", g)("blue", b);
+	*this = Color(r, g, b);	
+}
+
 RGBA operator*(int alpha, Color c)
 {
 	RGBA r;
diff --git a/uppsrc/Core/Color.h b/uppsrc/Core/Color.h
index de4e83f35..bf162f2ff 100644
--- a/uppsrc/Core/Color.h
+++ b/uppsrc/Core/Color.h
@@ -45,6 +45,7 @@ public:
 	bool     operator!=(Color c) const { return color != c.color; }
 
 	void     Serialize(Stream& s)      { s % color; }
+	void     Jsonize(JsonIO& jio);
 
 	Color()                            { SetNull(); }
 	Color(int r, int g, int b)         { color = RGB(r, g, b); }
diff --git a/uppsrc/Core/JSON.cpp b/uppsrc/Core/JSON.cpp
index f23ac2e9a..9edc5a035 100644
--- a/uppsrc/Core/JSON.cpp
+++ b/uppsrc/Core/JSON.cpp
@@ -249,10 +249,16 @@ template<> void Jsonize(JsonIO& io, Date& var)
 			return;
 		}
 		if(IsString(v)) {
-			Date d = ScanDate("ymd", (String)v);
-			if(!IsNull(d)) {
-				var = d;
-				return;
+			String text = v;
+			if(text.GetCount() > 6) {
+				Date d;
+				d.year = ScanInt(text.Left(4));
+				d.month = ScanInt(text.Mid(4, 2));
+				d.day = ScanInt(text.Mid(6));
+				if(var.IsValid()) {
+					var = d;
+					return;
+				}
 			}
 		}
 		throw JsonizeError("string expected for Date value");
@@ -261,7 +267,7 @@ template<> void Jsonize(JsonIO& io, Date& var)
 		if(IsNull(var))
 			io.Set(Null);
 		else
-			io.Set(Format("%04d-%02d-%02d", var.year, var.month, var.day));
+			io.Set(Format("%04d%02d%02d", var.year, var.month, var.day));
 }
 
 template<> void Jsonize(JsonIO& io, Time& var)
@@ -273,10 +279,19 @@ template<> void Jsonize(JsonIO& io, Time& var)
 			return;
 		}
 		if(IsString(v)) {
-			Time d = ScanTime("ymd", (String)v);
-			if(!IsNull(d)) {
-				var = d;
-				return;
+			String text = v;
+			if(text.GetCount() > 15) {
+				Time tm;
+				tm.year = ScanInt(text.Left(4));
+				tm.month = ScanInt(text.Mid(4, 2));
+				tm.day = ScanInt(text.Mid(6, 2));
+				tm.hour = ScanInt(text.Mid(9, 2));
+				tm.minute = ScanInt(text.Mid(12, 2));
+				tm.second = ScanInt(text.Mid(15));
+				if(var.IsValid()) {
+					var = tm;
+					return;
+				}
 			}
 		}
 		throw JsonizeError("string expected for Time value");
@@ -285,7 +300,7 @@ template<> void Jsonize(JsonIO& io, Time& var)
 		if(IsNull(var))
 			io.Set(Null);
 		else
-			io.Set(Format("%04d-%02d-%02d %02d:%02d:%02d",
+			io.Set(Format("%04d%02d%02d`T%02d:%02d:%02d",
 				          var.year, var.month, var.day, var.hour, var.minute, var.second));
 }
 
diff --git a/uppsrc/Core/Uuid.cpp b/uppsrc/Core/Uuid.cpp
index ce2e5d0a3..61b5751a3 100644
--- a/uppsrc/Core/Uuid.cpp
+++ b/uppsrc/Core/Uuid.cpp
@@ -19,6 +19,17 @@ void Uuid::Serialize(Stream& s) {
 	s / version % a % b %c % d;
 }
 
+void Uuid::Jsonize(JsonIO& jio)
+{
+	String h;
+	if(jio.IsStoring()) {
+		h = Format(*this);
+		jio.Set(h);
+	}
+	else
+		*this = ScanUuid((String)jio.Get());
+}
+
 Uuid Uuid::Create() {
 	Uuid ud;
 	ud.a = Random();
diff --git a/uppsrc/Core/Uuid.h b/uppsrc/Core/Uuid.h
index 79c28da11..d8b88bda4 100644
--- a/uppsrc/Core/Uuid.h
+++ b/uppsrc/Core/Uuid.h
@@ -3,6 +3,7 @@ struct Uuid : AssignValueTypeNo<Uuid, 50, Moveable<Uuid> > {
 
 	void Serialize(Stream& s);
 	void Xmlize(XmlIO& xio);
+	void Jsonize(JsonIO& jio);
 	bool IsNullInstance() const   { return a == 0 && b == 0 && c == 0 && d == 0; }
 	void SetNull()                { a = b = c = d = 0; }
 
diff --git a/uppsrc/Core/ValueUtil.cpp b/uppsrc/Core/ValueUtil.cpp
index 144408550..64fb0da31 100644
--- a/uppsrc/Core/ValueUtil.cpp
+++ b/uppsrc/Core/ValueUtil.cpp
@@ -36,6 +36,11 @@ void ValueArray::Data::Serialize(Stream& s)
 	s % data;
 }
 
+void ValueArray::Data::Jsonize(JsonIO& jio)
+{
+	Upp::Jsonize(jio, data);
+}
+
 void ValueArray::Data::Xmlize(XmlIO& io)
 {
 	Upp::Xmlize(io, data);
@@ -156,7 +161,7 @@ void ValueArray::Serialize(Stream& s) {
 
 void ValueArray::Jsonize(JsonIO& jio)
 {
-	if(s.IsLoading()) {
+	if(jio.IsLoading()) {
 		data->Release();
 		Create();
 	}
@@ -245,6 +250,38 @@ void ValueMap::Data::Xmlize(XmlIO& xio)
 	Upp::Xmlize(xio, value);
 }
 
+void ValueMap::Data::Jsonize(JsonIO& jio)
+{
+	if(jio.IsStoring()) {
+		ValueArray va;
+		int n = min(value.GetCount(), key.GetCount());
+		for(int i = 0; i < n; i++) {
+			ValueMap m;
+			m.Add("key", StoreAsJsonValue(key[i]));
+			m.Add("value", StoreAsJsonValue(value[i]));
+			va.Add(m);
+		}
+		jio.Set(va);
+	}
+	else {
+		Value va = jio.Get();
+		DDUMP(va);
+		key.Clear();
+		value.Clear();
+		for(int i = 0; i < va.GetCount(); i++) {
+			Value k, v;
+			DDUMP(va[i]);
+			DDUMP(va[i]["key"]);
+			LoadFromJsonValue(k, va[i]["key"]);
+			LoadFromJsonValue(v, va[i]["value"]);
+			DDUMP(k);
+			DDUMP(v);
+			key.Add(k);
+			value.Add(v);
+		}
+	}
+}
+
 unsigned ValueMap::Data::GetHashValue() const {
 	CombineHash w(key.GetCount());
 	for(int i = 0; i < key.GetCount(); i++)
@@ -365,6 +402,16 @@ void ValueMap::Serialize(Stream& s) {
 	data->Serialize(s);
 }
 
+void ValueMap::Jsonize(JsonIO& jio)
+{
+	if(jio.IsLoading()) {
+		data->Release();
+		Create();
+	}
+	data->Jsonize(jio);
+}
+
+
 ValueMap::~ValueMap() {
 	ASSERT(data->GetRefCount() > 0);
 	data->Release();
diff --git a/uppsrc/Core/ValueUtil.h b/uppsrc/Core/ValueUtil.h
index 916644bdc..0a8623c70 100644
--- a/uppsrc/Core/ValueUtil.h
+++ b/uppsrc/Core/ValueUtil.h
@@ -239,6 +239,7 @@ class ValueMap : AssignValueTypeNo<ValueMap, VALUEMAP_V, Moveable<ValueMap> >{
 		virtual bool       IsNull() const;
 		virtual void       Serialize(Stream& s);
 		virtual void       Xmlize(XmlIO& xio);
+		virtual void       Jsonize(JsonIO& jio);
 		virtual unsigned   GetHashValue() const;
 		virtual bool       IsEqual(const Value::Void *p);
 		virtual String     AsString() const;
@@ -311,6 +312,7 @@ public:
 
 	unsigned GetHashValue() const                 { return data->GetHashValue(); }
 	void     Serialize(Stream& s);
+	void     Jsonize(JsonIO& jio);
 	String   ToString() const                     { return data->AsString(); }
 
 	bool operator==(const ValueMap& v) const;