diff --git a/box.sh b/box.sh
index 8d28b7a..5fbf41b 100644
--- a/box.sh
+++ b/box.sh
@@ -13,16 +13,59 @@ function printtop () {
 	printf("%s\n", blank)
 }
 
+function printline(a)
+{
+	printf("* %s%*s *\n", a, maxlength - length(a), "")
+}
+
+# return the string a, with the character at pos, replaced with chr
+function replace(a, pos, chr)
+{
+	return substr(a, 1, pos - 1) chr substr(a, pos + 1)
+}
+
 output == 1 && FNR == 1 {
 	printtop()
 	printf("* %*s *\n", maxlength, "")
+
+	prevline = $0
+	next
 }
 
 output == 1 {
-	printf("* %s%*s *\n", $0, maxlength - length, "")
+	# fix up horizontal issues
+	gsub("\\|-", "+-", prevline)
+	gsub("\\| -", "+--", prevline)
+	gsub("-\\|", "-+", prevline)
+	gsub("- \\|", "--+", prevline)
+
+	# Fix up vertical issues
+
+	# first fix edges from below
+	r = split($0, a, "|")
+	pos = 0
+	for (i = 2; i <= r; i++) {
+		pos += length(a[i - 1]) + 1
+		if (substr(prevline, pos, 1) == "-")
+			prevline = replace(prevline, pos, "+")
+	}
+
+	# fix edges from above
+	r = split(prevline, a, "|")
+	pos = 0
+	for (i = 2; i <= r; i++) {
+		pos += length(a[i - 1]) + 1
+		if (substr($0, pos, 1) == "-")
+			$0 = replace($0, pos, "+")
+	}
+
+	printline(prevline)
+
+	prevline = $0
 }
 
 END {
+	printline(prevline)
 	printf("* %*s *\n", maxlength, "")
 	printtop()
 }