diff --git a/Changes b/Changes
index 9ec22e3..ab138b2 100644
--- a/Changes
+++ b/Changes
@@ -1,4 +1,6 @@
 Revision history for Perl module Neo4j::Bolt
+0.4202 2021-02-24
+    - Fix rare string encoding issues (#38, #39)
 0.4201 2021-01-20
     - Common types for Neo4j objects between Bolt and Driver (Arne)
     - Update (c)
diff --git a/Makefile.PL b/Makefile.PL
index c80a305..3b5e0e3 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -53,7 +53,7 @@ if ($neo_info) {
 WriteMakefile(
   NAME => 'Neo4j::Bolt',
   VERSION_FROM => 'lib/Neo4j/Bolt.pm',
-  MIN_PERL_VERSION => '5.010',
+  MIN_PERL_VERSION => '5.010001',
   CONFIGURE_REQUIRES => {
     'Alien::OpenSSL' => 0,
     'ExtUtils::MakeMaker' => '7.12',
@@ -67,7 +67,6 @@ WriteMakefile(
     'Alien::OpenSSL' => 0,
     'Neo4j::Client' => '0.46',
     'Neo4j::Types' => '1.00',
-    'parent' => 0,  # parent was first released with perl v5.10.1
     'JSON::PP' => 0,
     'URI' => 0,
     'XSLoader' => '0.14',  # XSLoader::load()
diff --git a/lib/Neo4j/Bolt.pm b/lib/Neo4j/Bolt.pm
index d77e6c7..b8bb4e3 100644
--- a/lib/Neo4j/Bolt.pm
+++ b/lib/Neo4j/Bolt.pm
@@ -2,7 +2,7 @@ package Neo4j::Bolt;
 use Cwd qw/realpath getcwd/;
 
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require Neo4j::Bolt::Cxn;
   require Neo4j::Bolt::Txn;
   require Neo4j::Bolt::ResultStream;
diff --git a/lib/Neo4j/Bolt/CResultStream.pm b/lib/Neo4j/Bolt/CResultStream.pm
index 08b2a97..31f8582 100644
--- a/lib/Neo4j/Bolt/CResultStream.pm
+++ b/lib/Neo4j/Bolt/CResultStream.pm
@@ -1,7 +1,7 @@
 package
   Neo4j::Bolt::CResultStream;
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require XSLoader;
   XSLoader::load();
 }
diff --git a/lib/Neo4j/Bolt/CTypeHandlers.pm b/lib/Neo4j/Bolt/CTypeHandlers.pm
index 2b95a83..ca9b8bb 100644
--- a/lib/Neo4j/Bolt/CTypeHandlers.pm
+++ b/lib/Neo4j/Bolt/CTypeHandlers.pm
@@ -1,6 +1,6 @@
 package Neo4j::Bolt::CTypeHandlers;
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require XSLoader;
   XSLoader::load();
 }
diff --git a/lib/Neo4j/Bolt/CTypeHandlers.xs b/lib/Neo4j/Bolt/CTypeHandlers.xs
index cc2f003..d102598 100644
--- a/lib/Neo4j/Bolt/CTypeHandlers.xs
+++ b/lib/Neo4j/Bolt/CTypeHandlers.xs
@@ -72,11 +72,15 @@ neo4j_value_t SVnv_to_neo4j_float (SV *sv) {
 neo4j_value_t SVpv_to_neo4j_string (SV *sv) {
   STRLEN len;
   char *k0,*k;
+  SV *sv2;
   k = SvPV(sv,len);
+  // create duplicate to keep SvPVutf8 from changing the original SV
+  sv2 = newSVpvn_flags(k, len, SvFLAGS(sv) & SVf_UTF8 | SVs_TEMP);
+  k = SvPVutf8(sv2, len);
   Newx(k0,len+1,char);
-  strncpy(k0,k,(size_t) len);
+  memcpy(k0,k,(size_t) len);
   *(k0+len) = 0;
-  return neo4j_string(k0);
+  return neo4j_ustring(k0, len);
 }
 
 neo4j_value_t SV_to_neo4j_value(SV *sv) {
@@ -158,8 +162,9 @@ neo4j_value_t AV_to_neo4j_list(AV *av) {
 neo4j_value_t HV_to_neo4j_map (HV *hv) {
   HE *ent;
   char *k,*k0;
-  SV *v;
-  int n,retlen;
+  SV *v,*ksv;
+  int n;
+  STRLEN retlen;
   neo4j_map_entry_t *map_ents;
   if (!HvTOTALKEYS(hv)) {
     return neo4j_null;
@@ -168,9 +173,10 @@ neo4j_value_t HV_to_neo4j_map (HV *hv) {
   hv_iterinit(hv);
   n=0;
   while ((ent = hv_iternext(hv))) {
-    k = hv_iterkey(ent,&retlen);
+    ksv = hv_iterkeysv(ent);
+    k = SvPVutf8(ksv, retlen);
     Newx(k0,retlen+1,char);
-    strncpy(k0,k,retlen);
+    memcpy(k0,k,retlen);
     *(k0+retlen)=0;
     map_ents[n] = neo4j_map_entry( k0, SV_to_neo4j_value(hv_iterval(hv,ent)));
     n++;
@@ -298,9 +304,11 @@ SV* neo4j_int_to_SViv( neo4j_value_t value ) {
 }
 
 SV* neo4j_string_to_SVpv( neo4j_value_t value ) {
+  STRLEN len;
   SV* pv;
-  pv = newSVpv(neo4j_string_to_alloc_str(value), 0);
-  SvUTF8_on(pv);  // depends on libneo4j-client output being valid UTF-8, always
+  len = neo4j_string_length(value);
+  pv = newSVpvn(neo4j_string_to_alloc_str(value), len);
+  sv_utf8_decode(pv);
   return pv;
 }
 
@@ -354,6 +362,7 @@ AV* neo4j_list_to_AV( neo4j_value_t value ) {
 
 HV* neo4j_map_to_HV( neo4j_value_t value ) {
   int i,n;
+  I32 klen;
   char *ks;
   const neo4j_map_entry_t *entry;
   HV *hv;
@@ -365,8 +374,11 @@ HV* neo4j_map_to_HV( neo4j_value_t value ) {
     ks = neo4j_string_to_alloc_str(entry->key);
     sv = neo4j_value_to_SV(entry->value);
     SvREFCNT_inc(sv);
-    if (hv_store(hv, ks, neo4j_string_length(entry->key), sv,0) ==
-	NULL) {
+    klen = neo4j_string_length(entry->key);
+    if (! is_utf8_invariant_string((U8 *)ks, (STRLEN)klen)) {
+      klen = -klen;
+    }
+    if (hv_store(hv, ks, klen, sv, 0) == NULL) {
       SvREFCNT_dec(sv);
       fprintf(stderr, "Failed to create hash entry for key '%s'\n",ks);
     }
diff --git a/lib/Neo4j/Bolt/Cxn.pm b/lib/Neo4j/Bolt/Cxn.pm
index f4ea05b..b2977f2 100644
--- a/lib/Neo4j/Bolt/Cxn.pm
+++ b/lib/Neo4j/Bolt/Cxn.pm
@@ -2,7 +2,7 @@ package Neo4j::Bolt::Cxn;
 use Carp qw/croak/;
 
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require Neo4j::Bolt::CTypeHandlers;
   require Neo4j::Bolt::ResultStream;
   require XSLoader;
@@ -27,6 +27,7 @@ sub run_query {
     croak "Arg 2 should be a hashref of { param => $value, ... }";
   }
   croak "No connection" unless $self->connected;
+  utf8::upgrade($query);
   return $self->run_query_($query, $parms // {}, 0, $db // default_db);
 }
 
@@ -40,6 +41,7 @@ sub send_query {
     croak "Arg 2 should be a hashref of { param => $value, ... }";
   }
   croak "No connection" unless $self->connected;
+  utf8::upgrade($query);
   return $self->run_query_($query, $parms ? $parms : {}, 1, $db // default_db );
 }
 
diff --git a/lib/Neo4j/Bolt/NeoValue.pm b/lib/Neo4j/Bolt/NeoValue.pm
index 4b30468..b218cba 100644
--- a/lib/Neo4j/Bolt/NeoValue.pm
+++ b/lib/Neo4j/Bolt/NeoValue.pm
@@ -1,7 +1,7 @@
 package Neo4j::Bolt::NeoValue;
 
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require Neo4j::Bolt::CTypeHandlers;
   require Neo4j::Bolt::CResultStream;
   require XSLoader;
diff --git a/lib/Neo4j/Bolt/Node.pm b/lib/Neo4j/Bolt/Node.pm
index 4b84e54..a6a2881 100644
--- a/lib/Neo4j/Bolt/Node.pm
+++ b/lib/Neo4j/Bolt/Node.pm
@@ -1,7 +1,7 @@
 package Neo4j::Bolt::Node;
 # ABSTRACT: Representation of Neo4j Node
 
-$Neo4j::Bolt::Node::VERSION = '0.4201';
+$Neo4j::Bolt::Node::VERSION = '0.4202';
 
 use strict;
 use warnings;
diff --git a/lib/Neo4j/Bolt/Path.pm b/lib/Neo4j/Bolt/Path.pm
index 2abfa53..9263f90 100644
--- a/lib/Neo4j/Bolt/Path.pm
+++ b/lib/Neo4j/Bolt/Path.pm
@@ -1,7 +1,7 @@
 package Neo4j::Bolt::Path;
 # ABSTRACT: Representation of Neo4j Path
 
-$Neo4j::Bolt::Path::VERSION = '0.4201';
+$Neo4j::Bolt::Path::VERSION = '0.4202';
 
 use strict;
 use warnings;
diff --git a/lib/Neo4j/Bolt/Relationship.pm b/lib/Neo4j/Bolt/Relationship.pm
index ee5b533..e883129 100644
--- a/lib/Neo4j/Bolt/Relationship.pm
+++ b/lib/Neo4j/Bolt/Relationship.pm
@@ -1,7 +1,7 @@
 package Neo4j::Bolt::Relationship;
 # ABSTRACT: Representation of Neo4j Relationship
 
-$Neo4j::Bolt::Relationship::VERSION = '0.4201';
+$Neo4j::Bolt::Relationship::VERSION = '0.4202';
 
 use strict;
 use warnings;
diff --git a/lib/Neo4j/Bolt/ResultStream.pm b/lib/Neo4j/Bolt/ResultStream.pm
index f35edf3..783e0ed 100644
--- a/lib/Neo4j/Bolt/ResultStream.pm
+++ b/lib/Neo4j/Bolt/ResultStream.pm
@@ -2,7 +2,7 @@ package Neo4j::Bolt::ResultStream;
 # use Neo4j::Client;
 
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require Neo4j::Bolt::Cxn;
   require Neo4j::Bolt::CResultStream;
   require XSLoader;
diff --git a/lib/Neo4j/Bolt/Txn.pm b/lib/Neo4j/Bolt/Txn.pm
index b03c7ec..0eeb24e 100644
--- a/lib/Neo4j/Bolt/Txn.pm
+++ b/lib/Neo4j/Bolt/Txn.pm
@@ -2,7 +2,7 @@ package Neo4j::Bolt::Txn;
 use Carp qw/croak/;
 
 BEGIN {
-  our $VERSION = "0.4201";
+  our $VERSION = "0.4202";
   require Neo4j::Bolt::CTypeHandlers;
   require Neo4j::Bolt::ResultStream;  
   require XSLoader;
@@ -44,6 +44,7 @@ sub run_query {
   if ($parms && !(ref $parms == 'HASH')) {
     die "Arg 2 should be a hashref of { param => $value, ... }";
   }
+  utf8::upgrade($query);
   return $self->run_query_($query, $parms ? $parms : {}, 0);
 }
 
@@ -56,6 +57,7 @@ sub send_query {
   if ($parms && !(ref $parms == 'HASH')) {
     die "Arg 2 should be a hashref of { param => $value, ... }";
   }
+  utf8::upgrade($query);
   return $self->run_query_($query, $parms // {}, 1);
 }
 
diff --git a/t/008_strings.t b/t/008_strings.t
new file mode 100644
index 0000000..28e2f53
--- /dev/null
+++ b/t/008_strings.t
@@ -0,0 +1,160 @@
+use strict;
+use warnings;
+use Test::More;
+use Encode ();
+use File::Spec;
+use URI;
+use Neo4j::Bolt;
+use Neo4j::Bolt::NeoValue;
+
+# String encoding, esp. to and from UTF-8
+
+plan tests => 7 + 14 + 18;
+
+my ($i, $o, $v);
+
+sub SVf_UTF8 { utf8::is_utf8(shift) ? 'U' : 'B' }
+sub to_hex { join ' ', SVf_UTF8($_[0]), map { sprintf "%02x", ord $_ } split //, $_[0] }
+sub to_str { my $s = shift; $s =~ s/([[:xdigit:]]{2})/chr(hex($1))/eg; Encode::_utf8_on($s); $s }
+
+# GitHub issue #39
+$i = "A\0B";
+$v = Neo4j::Bolt::NeoValue->_new_from_perl($i);
+is to_hex($v->_as_perl), to_hex($i), "NUL byte in string";
+
+# GitHub issue #38
+
+# strings with Perl byte semantics shouldn't be treated as Unicode strings
+no utf8;
+$i = "\x{c4}\x{80}";  # a sequence of two bytes that also happens to be valid UTF-8 for U+0100
+eval { Encode::_utf8_off($i) };  # SVf_UTF8 should already be off, but why not try to make sure
+$o = $i;
+$v = Neo4j::Bolt::NeoValue->_new_from_perl($i);
+$v = $v->_as_perl;
+isnt to_hex($v), "U 100", "bytes in string";
+ok utf8::is_utf8($v), "bytes in string - Neo4j returns UTF-8";
+
+# same for map keys
+# (which are strings as well, but use a different code path in CTypeHandlers)
+$v = Neo4j::Bolt::NeoValue->_new_from_perl( {$i => 1} );
+$v = ( keys %{$v->_as_perl} )[0];
+isnt to_hex($v), "U 100", "bytes in map key";
+ok utf8::is_utf8($v), "bytes in map key - Neo4j returns UTF-8";
+is to_hex($i), to_hex($o), "input SV unchanged";
+
+# Note: The exact result in the tests above depends on the native single
+# byte encoding that Perl assumes for this file under "no utf8;". This
+# encoding is usually Latin-1 (which would yield "U c4 80"), but could
+# be anything else. However, we know "U 100" means that the non-Unicode
+# bytes were interpreted as Unicode UTF-8, which is definitely wrong.
+
+# real Unicode char in map key
+use utf8;
+$i = "\x{100}";
+eval { Encode::_utf8_on($i) };  # SVf_UTF8 should already be on, but why not try to make sure
+$v = Neo4j::Bolt::NeoValue->_new_from_perl( {$i => 1} );
+$v = ( keys %{$v->_as_perl} )[0];
+is to_hex($v), to_hex($i), "Unicode char in map key";
+
+# byte sequences that aren't valid UTF-8 shouldn't be treated as such (RFC3629)
+my @seq = (
+  40   => "B 40",  # valid UTF-8 for U+0040
+  C2BD => "U bd",  # valid UTF-8 for U+00BD
+  C1   => "B c1",  # invalid byte
+  F5   => "B f5",  # invalid byte
+  FF   => "B ff",  # invalid byte
+  A0   => "B a0",      # unexpected continuation byte
+  5885 => "B 58 85",   # unexpected continuation byte
+  D0D1 => "B d0 d1",   # non-continuation byte before end of character
+  C838 => "B c8 38",   # non-continuation byte before end of character
+  EEBB => "B ee bb",   # ending before end of character
+  EDBFBF   => "U dfff",    # invalid UTF-8 code point, but allowed in Perl
+  F4908080 => "U 110000",  # invalid UTF-8 code point, but allowed in Perl
+  F08282AC => "B f0 82 82 ac",  # overlong encoding (for U+20AC)
+  C080     => "B c0 80",        # overlong encoding (for U+0000)
+);
+for (my $k = 0; $k < @seq; ) {
+  $i = $seq[$k++];
+  $o = $seq[$k++];
+  $v = Neo4j::Bolt::NeoValue->_new_from_perl( to_str($i) );
+  is to_hex($v->_as_perl), $o, "byte sequence $i";
+}
+
+# Cypher statements
+# (which are strings as well, but use a different code path in Cxn/Txn)
+
+my $neo_info;
+my $nif = File::Spec->catfile('t','neo_info');
+if (-e $nif ) {
+    local $/;
+    open my $fh, "<", $nif or die $!;
+    my $val = <$fh>;
+    $val =~ s/^.*?(=.*)$/\$neo_info $1/s;
+    eval $val;
+}
+
+my $cxn;
+if (defined $neo_info && $neo_info->{tests}) {
+  my $url = URI->new("bolt://$neo_info->{host}");
+  $url->userinfo("$neo_info->{user}:$neo_info->{pass}") if $neo_info->{user};
+  $cxn = Neo4j::Bolt->connect("$url");
+}
+
+SKIP: {
+  skip "statement tests require server connection", 18 unless $cxn && $cxn->connected;
+  my ($q, $id);
+  
+  use utf8;
+  $i = "\x{100}";
+  $q = "RETURN '$i'";
+  eval { Encode::_utf8_on($q) };  # SVf_UTF8 should already be on...
+  $v = ($cxn->run_query($q)->fetch_next)[0];
+  is to_hex($v), to_hex($i), "Unicode char in Cxn run_query";
+  (undef, $v) = $cxn->do_query($q);
+  is to_hex($v->[0]), to_hex($i), "Unicode char in Cxn do_query";
+  
+  no utf8;
+  $i = "\x{c4}\x{80}";
+  $q = "RETURN '$i'";
+  eval { Encode::_utf8_off($q) };  # SVf_UTF8 should already be off...
+  $v = ($cxn->run_query($q)->fetch_next)[0];
+  isnt to_hex($v), "U 100", "bytes in Cxn run_query - input not treated as UTF-8";
+  ok utf8::is_utf8($v), "bytes in Cxn run_query - output encoded in UTF-8";
+  (undef, $v) = $cxn->do_query($q);
+  isnt to_hex($v->[0]), "U 100", "bytes in Cxn do_query - input not treated as UTF-8";
+  ok utf8::is_utf8($v->[0]), "bytes in Cxn do_query - output encoded in UTF-8";
+  
+  skip "transaction tests require Bolt version 3+", 12 if $cxn->protocol_version lt "3.0";
+  ok my $txn = Neo4j::Bolt::Txn->new($cxn), "begin transaction";
+  
+  use utf8;
+  $i = "\x{100}";
+  eval { Encode::_utf8_on($i) };  # SVf_UTF8 should already be on...
+  (undef, $v) = $txn->do_query("CREATE (n) RETURN '$i', id(n)");
+  is to_hex($v->[0]), to_hex($i), "Unicode char in Txn do_query";
+  $id = {id => $v->[1]};
+  $v = $txn->send_query("MATCH (n) WHERE id(n) = \$id SET n.t = '$i'", $id);
+  ok $v->success(), "Txn send_query 1";
+  ($v, $o) = $txn->run_query("MATCH (n) WHERE id(n) = \$id RETURN n.t, '$i'", $id)->fetch_next;
+  is to_hex($v), to_hex($i), "Unicode char in Txn send_query";
+  is to_hex($o), to_hex($i), "Unicode char in Txn run_query";
+  
+  no utf8;
+  $i = "\x{c4}\x{80}";
+  eval { Encode::_utf8_off($i) };  # SVf_UTF8 should already be off...
+  (undef, $v) = $txn->do_query("CREATE (n) RETURN '$i', id(n)");
+  isnt to_hex($v->[0]), "U 100", "bytes in Txn do_query - input not treated as UTF-8";
+  ok utf8::is_utf8($v->[0]), "bytes in Txn do_query - output encoded in UTF-8";
+  $id = {id => $v->[1]};
+  $v = $txn->send_query("MATCH (n) WHERE id(n) = \$id SET n.t = '$i'", $id);
+  ok $v->success(), "Txn send_query 2";
+  ($v, $o) = $txn->run_query("MATCH (n) WHERE id(n) = \$id RETURN n.t, '$i'", $id)->fetch_next;
+  isnt to_hex($v), "U 100", "bytes in Txn send_query - input not treated as UTF-8";
+  ok utf8::is_utf8($v), "bytes in Txn send_query - output encoded in UTF-8";
+  isnt to_hex($o), "U 100", "bytes in Txn run_query - input not treated as UTF-8";
+  ok utf8::is_utf8($o), "bytes in Txn run_query - output encoded in UTF-8";
+  
+  $txn->rollback;
+}
+
+done_testing;