diff --git a/src/ucd-tools/CHANGELOG.md b/src/ucd-tools/CHANGELOG.md
index db784527..f2dbf341 100644
--- a/src/ucd-tools/CHANGELOG.md
+++ b/src/ucd-tools/CHANGELOG.md
@@ -7,6 +7,10 @@ These are eSpeak NG specific modifications to the `ucd-tools` project:
 *  `data/espeak-ng` data files for eSpeak NG extended data.
 *  espeak-ng PropList property lookup as part of the `ucd_property` API.
 
+## (In Development)
+
+*  Make the ispunct ctype compatibility implementation conformant.
+
 ## 10.0.0 - 2017-06-25
 
 *  Add `iswblank` and `iswxdigit` compatibility.
diff --git a/src/ucd-tools/README.md b/src/ucd-tools/README.md
index 6a583766..40ae1793 100644
--- a/src/ucd-tools/README.md
+++ b/src/ucd-tools/README.md
@@ -17,8 +17,8 @@ this information within a C or C++ program.
 
 The project uses and supports the following sources of Unicode codepoint data:
 
-*  [Unicode Character Database](http://www.unicode.org/Public/9.0.0/ucd/) 9.0.0
-*  [Unicode Emoji](http://www.unicode.org/Public/emoji/4.0/) 4.0 (UTR #51)
+*  [Unicode Character Database](http://www.unicode.org/Public/10.0.0/ucd/) 10.0.0
+*  [Unicode Emoji](http://www.unicode.org/Public/emoji/5.0/) 5.0 (UTR #51)
 *  [ConScript Unicode Registry](http://www.evertype.com/standards/csur/)
 
 ## Build Dependencies
diff --git a/src/ucd-tools/src/ctype.c b/src/ucd-tools/src/ctype.c
index 42bb9f58..ac6a37ea 100644
--- a/src/ucd-tools/src/ctype.c
+++ b/src/ucd-tools/src/ctype.c
@@ -1,6 +1,6 @@
 /* ctype-style APIs.
  *
- * Copyright (C) 2012-2017 Reece H. Dunn
+ * Copyright (C) 2012-2018 Reece H. Dunn
  *
  * This file is part of ucd-tools.
  *
@@ -151,19 +151,7 @@ int ucd_isprint(codepoint_t c)
 
 int ucd_ispunct(codepoint_t c)
 {
-	switch (ucd_lookup_category(c))
-	{
-	case UCD_CATEGORY_Pc:
-	case UCD_CATEGORY_Pd:
-	case UCD_CATEGORY_Pe:
-	case UCD_CATEGORY_Pf:
-	case UCD_CATEGORY_Pi:
-	case UCD_CATEGORY_Po:
-	case UCD_CATEGORY_Ps:
-		return 1;
-	default:
-		return 0;
-	}
+	return ucd_isgraph(c) && !ucd_isalnum(c);
 }
 
 int ucd_isspace(codepoint_t c)
diff --git a/src/ucd-tools/tools/printdata.py b/src/ucd-tools/tools/printdata.py
index ea306466..3b90dc76 100755
--- a/src/ucd-tools/tools/printdata.py
+++ b/src/ucd-tools/tools/printdata.py
@@ -79,10 +79,7 @@ def isblank(data): # word separator
 		return 0
 
 def ispunct(data):
-	if data.get('GeneralCategory', 'Cn')[0] in 'P':
-		return 1
-	else:
-		return 0
+	return 1 if isgraph(data) and not isalnum(data) else 0
 
 def isprint(data):
 	if data.get('GeneralCategory', 'Cn')[0] in 'LMNPSZ': # not in 'CI'