diff --git a/src/ccnx-selectors.cpp b/src/ccnx-selectors.cpp
new file mode 100644
index 0000000..001c1b7
--- /dev/null
+++ b/src/ccnx-selectors.cpp
@@ -0,0 +1,120 @@
+#include "ccnx-selectors.h"
+#include "ccnx-common.h"
+#include <boost/lexical_cast.hpp>
+
+namespace Ccnx {
+
+Selectors::Selectors()
+          : m_maxSuffixComps(-1)
+          , m_minSuffixComps(-1)
+          , m_answerOriginKind(AOK_DEFAULT)
+          , m_interestLifetime(-1.0)
+          , m_scope(-1)
+          , m_childSelector(DEFAULT)
+{
+}
+
+Selectors::Selectors(const Selectors &other)
+{
+  m_maxSuffixComps = other.m_maxSuffixComps;
+  m_minSuffixComps = other.m_minSuffixComps;
+  m_answerOriginKind = other.m_answerOriginKind;
+  m_interestLifetime = other.m_interestLifetime;
+  m_scope = other.m_scope;
+  m_childSelector = other.m_childSelector;
+  m_publisherPublicKeyDigest = other.m_publisherPublicKeyDigest;
+}
+
+bool
+Selectors::operator == (const Selectors &other)
+{
+  return m_maxSuffixComps == other.m_maxSuffixComps
+         && m_minSuffixComps == other.m_minSuffixComps
+         && m_answerOriginKind == other.m_answerOriginKind
+         && (m_interestLifetime - other.m_interestLifetime) < 10e-4
+         && m_scope == other.m_scope
+         && m_childSelector == other.m_childSelector;
+}
+
+bool
+Selectors::isEmpty() const
+{
+  return m_maxSuffixComps == -1
+         && m_minSuffixComps == -1
+         && m_answerOriginKind == AOK_DEFAULT
+         && (m_interestLifetime - (-1.0)) < 10e-4
+         && m_scope == -1
+         && m_childSelector == DEFAULT;
+}
+
+
+CcnxCharbufPtr
+Selectors::toCcnxCharbuf() const
+{
+  if (isEmpty())
+  {
+    return CcnxCharbuf::Null;
+  }
+  CcnxCharbufPtr ptr(new CcnxCharbuf());
+  ccn_charbuf *cbuf = ptr->getBuf();
+  ccn_charbuf_append_tt(cbuf, CCN_DTAG_Interest, CCN_DTAG);
+  ccn_charbuf_append_tt(cbuf, CCN_DTAG_Name, CCN_DTAG);
+  ccn_charbuf_append_closer(cbuf); // </Name>
+
+  if (m_maxSuffixComps < m_minSuffixComps)
+  {
+    boost::throw_exception(InterestSelectorException() << error_info_str("MaxSuffixComps = " + boost::lexical_cast<string>(m_maxSuffixComps) + " is smaller than  MinSuffixComps = " + boost::lexical_cast<string>(m_minSuffixComps)));
+  }
+
+  if (m_maxSuffixComps > 0)
+  {
+    ccnb_tagged_putf(cbuf, CCN_DTAG_MaxSuffixComponents, "%d", m_maxSuffixComps);
+  }
+
+  if (m_minSuffixComps > 0)
+  {
+    ccnb_tagged_putf(cbuf, CCN_DTAG_MinSuffixComponents, "%d", m_minSuffixComps);
+  }
+
+  if (m_answerOriginKind != AOK_DEFAULT)
+  {
+    // it was not using "ccnb_tagged_putf" in ccnx c code, no idea why
+    ccn_charbuf_append_tt(cbuf, CCN_DTAG_AnswerOriginKind, CCN_DTAG);
+    ccnb_append_number(cbuf, m_answerOriginKind);
+    ccn_charbuf_append_closer(cbuf); // <AnswerOriginKind>
+  }
+
+  if (m_scope != -1)
+  {
+    ccnb_tagged_putf(cbuf, CCN_DTAG_Scope, "%d", m_scope);
+  }
+
+  if (m_interestLifetime > 0.0)
+  {
+    // Ccnx timestamp unit is weird 1/4096 second
+    // this is from their code
+    unsigned lifetime = 4096 * (m_interestLifetime + 1.0/8192.0);
+    if (lifetime == 0 || lifetime > (30 << 12))
+    {
+      boost::throw_exception(InterestSelectorException() << error_info_str("Ccnx requires 0 < lifetime < 30.0. lifetime= " + boost::lexical_cast<string>(m_interestLifetime)));
+    }
+    unsigned char buf[3] = {0};
+    for (int i = sizeof(buf) - 1; i >= 0; i--, lifetime >>= 8)
+    {
+      buf[i] = lifetime & 0xff;
+    }
+    ccnb_append_tagged_blob(cbuf, CCN_DTAG_InterestLifetime, buf, sizeof(buf));
+  }
+
+  if (m_childSelector != DEFAULT)
+  {
+    ccnb_tagged_putf(cbuf, CCN_DTAG_ChildSelector, "%d", m_childSelector);
+  }
+
+
+  ccn_charbuf_append_closer(cbuf); // </Interest>
+
+  return ptr;
+}
+
+} // Ccnx