diff --git a/sys/net/network_layer/ng_ipv6/netif/ng_ipv6_netif.c b/sys/net/network_layer/ng_ipv6/netif/ng_ipv6_netif.c
index 044b32d960c0..b6647e2f8c06 100644
--- a/sys/net/network_layer/ng_ipv6/netif/ng_ipv6_netif.c
+++ b/sys/net/network_layer/ng_ipv6/netif/ng_ipv6_netif.c
@@ -468,6 +468,8 @@ static bool _create_candidate_set(ng_ipv6_netif_t *iface,
 {
     bool res = false;
 
+    DEBUG("gathering candidates\n");
+
     /* currently this implementation supports only addresses as source address
      * candidates assigned to this interface. Thus we assume all addresses to be
      * on interface @p iface */
@@ -476,6 +478,9 @@ static bool _create_candidate_set(ng_ipv6_netif_t *iface,
     for (int i = 0; i < NG_IPV6_NETIF_ADDR_NUMOF; i++) {
         ng_ipv6_netif_addr_t *iter = &(iface->addrs[i]);
 
+        DEBUG("Checking address: %s\n",
+              ng_ipv6_addr_to_str(addr_str, &(iter->addr), sizeof(addr_str)));
+
         /* "In any case, multicast addresses and the unspecified address MUST NOT
          *  be included in a candidate set."
          */
@@ -496,6 +501,7 @@ static bool _create_candidate_set(ng_ipv6_netif_t *iface,
          */
 
         /* put all other addresses into the candidate set */
+        DEBUG("add to candidate set\n");
         bf_set(candidate_set, i);
         res = true;
     }
@@ -524,19 +530,24 @@ static ng_ipv6_addr_t *_source_address_selection(ng_ipv6_netif_t *iface,
     BITFIELD(tiebreaker_tmp_set, candidate_set_len);
     memset(tiebreaker_tmp_set, 0, candidate_set_len);
     uint8_t tiebreaker_count = 0;
+    DEBUG("finding a the best match within the source address candidates\n");
 
     for (int i = 0; i < NG_IPV6_NETIF_ADDR_NUMOF; i++) {
         ng_ipv6_netif_addr_t *iter = &(iface->addrs[i]);
+        DEBUG("Checking address: %s\n",
+              ng_ipv6_addr_to_str(addr_str, &(iter->addr), sizeof(addr_str)));
         /* entries configured to unspecified address or those which are not
          * part of the candidate set can be ignored */
         if (ng_ipv6_addr_is_unspecified(&(iter->addr)) ||
             !(bf_isset(candidate_set, i))) {
+            DEBUG("Unspecified or not part of the candidate set - skipping\n");
             continue;
         }
 
         /* Rule 1: if we have an address configured that equals the destination
          * use this one as source */
         if (ng_ipv6_addr_equal(&(iter->addr), dest)) {
+            DEBUG("Ease one - rule 1\n");
             return &(iter->addr);
         }
 
@@ -559,12 +570,14 @@ static ng_ipv6_addr_t *_source_address_selection(ng_ipv6_netif_t *iface,
                 /* both global unicast */
                 (ng_ipv6_addr_is_global_unicast(dest) &&
                  ng_ipv6_addr_is_global_unicast(&(iter->addr)))) {
+            DEBUG("winner for rule 2 found\n");
             bf_set(rule2_tmp_set, i);
             rule2_hit++;
         }
 
         /* Rule 3: Avoid deprecated addresses. */
         if (iter->preferred > 0) {
+            DEBUG("winner for rule 3 found\n");
             bf_set(rule3_tmp_set, i);
             rule3_hit++;
         }
@@ -608,6 +621,7 @@ static ng_ipv6_addr_t *_source_address_selection(ng_ipv6_netif_t *iface,
     }
     /* check if we can use rule 3 as a tiebreaker for candidates winning in rule 2 */
     else if ((rule2_hit > 1) && (rule3_hit > 1)) {
+        DEBUG("Looking for a tiebreaker\n");
         for (int i = 0; i < candidate_set_len; i++) {
             if (bf_isset(rule2_tmp_set, i) && bf_isset(rule3_tmp_set, i)) {
                 bf_set(tiebreaker_tmp_set, i);
@@ -615,6 +629,7 @@ static ng_ipv6_addr_t *_source_address_selection(ng_ipv6_netif_t *iface,
             }
         }
         if (tiebreaker_count == 1) {
+            DEBUG("Found a match\n");
             int tmp = bf_get_first_set(tiebreaker_tmp_set, candidate_set_len);
             return &(iface->addrs[tmp].addr);
         }