diff --git a/configure.in b/configure.in
index dc8d6e0c2a..47c35d8b1c 100644
--- a/configure.in
+++ b/configure.in
@@ -123,6 +123,11 @@ AC_INIT(configure.in)
                     CPPFLAGS="${CPPFLAGS} -I/usr/local/include -I/usr/local/include/libnet11"
                     LDFLAGS="${LDFLAGS} -L/usr/local/lib -L/usr/local/lib/libnet11"
                     ;;
+           *-*-openbsd*)
+                    CFLAGS="${CFLAGS} -D__OpenBSD__"
+                    CPPFLAGS="${CPPFLAGS} -I/usr/local/include -I/usr/local/include/libnet-1.1"
+                    LDFLAGS="${LDFLAGS} -L/usr/local/lib -I/usr/local/lib/libnet-1.1"
+                    ;;
 	   *darwin*|*Darwin*)
                     CFLAGS="${CFLAGS} -DOS_DARWIN"
                     CPPFLAGS="${CPPFLAGS} -I/opt/local/include"
diff --git a/src/suricata-common.h b/src/suricata-common.h
index 5ebe1827b6..a002350258 100644
--- a/src/suricata-common.h
+++ b/src/suricata-common.h
@@ -97,14 +97,14 @@
 
 #include <sys/stat.h>
 
-#if HAVE_ARPA_INET_H
-#include <arpa/inet.h>
-#endif
-
 #if HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
 
+#if HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+
 #if HAVE_NETDB_H
 #include <netdb.h>
 #endif
diff --git a/src/threads.h b/src/threads.h
index 4c82d0fee0..8b83e4ed94 100644
--- a/src/threads.h
+++ b/src/threads.h
@@ -27,9 +27,11 @@
 #ifndef __THREADS_H__
 #define __THREADS_H__
 
-#ifdef OS_FREEBSD
+#if defined OS_FREEBSD || __OpenBSD__
 
+#if ! defined __OpenBSD__
 #include <sys/thr.h>
+#endif
 enum {
     PRIO_LOW = 2,
     PRIO_MEDIUM = 0,
@@ -99,6 +101,13 @@ enum {
     u_long tid = (u_long)tmpthid; \
     tid; \
 })
+#elif __OpenBSD__
+#define SCGetThreadIdLong(...) ({ \
+    pid_t tpid; \
+    tpid = getpid(); \
+    u_long tid = (u_long)tpid; \
+    tid; \
+})
 #elif OS_WIN32
 #define SCGetThreadIdLong(...) ({ \
     u_long tid = (u_long)GetCurrentThreadId(); \
@@ -361,7 +370,7 @@ enum {
  */
 #ifndef PR_SET_NAME /*PR_SET_NAME */
 #define SCSetThreadName(n)
-#elif OS_FREEBSD /* FreeBSD */
+#elif defined OS_FREEBSD || __OpenBSD__ /* FreeBSD or OpenBSD */
 /** \todo Add implementation for FreeBSD */
 #define SCSetThreadName(n)
 #elif OS_WIN32 /* Windows */
diff --git a/src/tm-threads.c b/src/tm-threads.c
index 77d3e996d9..1f14e143c2 100644
--- a/src/tm-threads.c
+++ b/src/tm-threads.c
@@ -664,13 +664,9 @@ void TmVarSlotSetFuncAppend(ThreadVars *tv, TmModule *tm, void *data) {
     }
 }
 
-#ifdef OS_WIN32
-static int SetCPUAffinitySet(uint32_t cs) {
-    return 0;
-}
-#else
+#if !defined OS_WIN32 && !defined __OpenBSD__
 static int SetCPUAffinitySet(cpu_set_t *cs) {
-#ifdef OS_FREEBSD
+#if  defined OS_FREEBSD
     int r = cpuset_setaffinity(CPU_LEVEL_WHICH,CPU_WHICH_TID,SCGetThreadIdLong(),sizeof(cpu_set_t),cs);
 #elif OS_DARWIN
     int r = thread_policy_set(mach_thread_self(), THREAD_AFFINITY_POLICY, (void*)cs, THREAD_AFFINITY_POLICY_COUNT);
@@ -696,11 +692,14 @@ static int SetCPUAffinitySet(cpu_set_t *cs) {
  * \retval 0 if all goes well; -1 if something is wrong
  */
 static int SetCPUAffinity(uint16_t cpuid) {
-
+#if !defined __OpenBSD__
     int cpu = (int)cpuid;
+#endif
 
 #ifdef OS_WIN32
 	DWORD cs = 1 << cpu;
+#elif defined __OpenBSD__
+    return 0;
 #else
     cpu_set_t cs;
 
@@ -717,7 +716,7 @@ static int SetCPUAffinity(uint16_t cpuid) {
     SCLogDebug("CPU Affinity for thread %lu set to CPU %" PRId32, SCGetThreadIdLong(), cpu);
 
     return 0;
-#else
+#elif !defined __OpenBSD__
     return SetCPUAffinitySet(&cs);
 #endif /* OS_WIN32 */
 }
@@ -802,6 +801,7 @@ TmEcode TmThreadSetupOptions(ThreadVars *tv) {
         SCLogInfo("Setting affinity for \"%s\" Module to cpu/core %"PRIu16", thread id %lu", tv->name, tv->cpu_affinity, SCGetThreadIdLong());
         SetCPUAffinity(tv->cpu_affinity);
     }
+#if !defined OS_WIN32 && !defined __OpenBSD__
     if (tv->thread_setup_flags & THREAD_SET_PRIORITY)
         TmThreadSetPrio(tv);
     if (tv->thread_setup_flags & THREAD_SET_AFFTYPE) {
@@ -827,6 +827,7 @@ TmEcode TmThreadSetupOptions(ThreadVars *tv) {
         }
         TmThreadSetPrio(tv);
     }
+#endif
     return TM_ECODE_OK;
 }
 
diff --git a/src/util-affinity.c b/src/util-affinity.c
index be6b12149e..28c72ab9a2 100644
--- a/src/util-affinity.c
+++ b/src/util-affinity.c
@@ -97,6 +97,7 @@ ThreadsAffinityType * GetAffinityTypeFromName(const char *name) {
     return NULL;
 }
 
+#if !defined OS_WIN32 && !defined __OpenBSD__
 static void AffinitySetupInit()
 {
     int i, j;
@@ -112,7 +113,6 @@ static void AffinitySetupInit()
         }
 	SCMutexInit(&thread_affinity[i].taf_mutex, NULL);
     }
-
     return;
 }
 
@@ -168,6 +168,7 @@ static void build_cpuset(ConfNode *node, cpu_set_t *cpu)
             break;
     }
 }
+#endif /* OS_WIN32 and __OpenBSD__ */
 
 /**
  * \brief Extract cpu affinity configuration from current config file
@@ -175,6 +176,7 @@ static void build_cpuset(ConfNode *node, cpu_set_t *cpu)
 
 void AffinitySetupLoadFromConfig()
 {
+#if !defined OS_WIN32 && !defined __OpenBSD__
     ConfNode *root = ConfGetNode("threading.cpu_affinity");
     ConfNode *affinity;
 
@@ -269,6 +271,7 @@ void AffinitySetupLoadFromConfig()
             }
         }
     }
+#endif /* OS_WIN32 and __OpenBSD__ */
 }
 
 /**
@@ -279,6 +282,7 @@ int AffinityGetNextCPU(ThreadsAffinityType *taf)
 {
     int ncpu = 0;
 
+#if !defined OS_WIN32 && !defined __OpenBSD__
     SCMutexLock(&taf->taf_mutex);
     ncpu = taf->lcpu;
     while (!CPU_ISSET(ncpu, &taf->cpu_set)) {
@@ -291,5 +295,6 @@ int AffinityGetNextCPU(ThreadsAffinityType *taf)
         taf->lcpu = 0;
     SCMutexUnlock(&taf->taf_mutex);
     SCLogInfo("Setting affinity on CPU %d", ncpu);
+#endif /* OS_WIN32 and __OpenBSD__ */
     return ncpu;
 }
diff --git a/src/util-affinity.h b/src/util-affinity.h
index 3edb7a3e44..d03252b651 100644
--- a/src/util-affinity.h
+++ b/src/util-affinity.h
@@ -25,14 +25,18 @@
 #define __UTIL_AFFINITY_H__
 #include "suricata-common.h"
 
-#ifdef OS_FREEBSD
+#if defined OS_FREEBSD
 #include <sched.h>
 #include <sys/param.h>
 #include <sys/resource.h>
 #include <sys/cpuset.h>
 #include <sys/thr.h>
 #define cpu_set_t cpuset_t
-#elif OS_DARWIN
+#elif defined __OpenBSD__
+#include <sched.h>
+#include <sys/param.h>
+#include <sys/resource.h>
+#elif defined OS_DARWIN
 #include <mach/mach.h>
 #include <mach/mach_init.h>
 #include <mach/thread_policy.h>
@@ -62,13 +66,17 @@ enum {
 
 typedef struct ThreadsAffinityType_ {
     char *name;
+#if !defined OS_WIN32 && !defined __OpenBSD__
     cpu_set_t cpu_set;
+#endif
     uint8_t mode_flag;
     int prio;
     int nb_threads;
+#if !defined OS_WIN32 && !defined __OpenBSD__
     cpu_set_t lowprio_cpu;
     cpu_set_t medprio_cpu;
     cpu_set_t hiprio_cpu;
+#endif
     SCMutex taf_mutex;
     uint16_t lcpu; /* use by exclusive mode */
 } ThreadsAffinityType;
diff --git a/src/util-byte.h b/src/util-byte.h
index 4f702b613f..443bcd1ab4 100644
--- a/src/util-byte.h
+++ b/src/util-byte.h
@@ -35,6 +35,11 @@
 #define SCByteSwap16(x) bswap16(x)
 #define SCByteSwap32(x) bswap32(x)
 #define SCByteSwap64(x) bswap64(x)
+#elif defined __OpenBSD__
+#include <sys/types.h>
+#define SCByteSwap16(x) swap16(x)
+#define SCByteSwap32(x) swap32(x)
+#define SCByteSwap64(x) swap64(x)
 #elif OS_DARWIN
 #include <libkern/OSByteOrder.h>
 #define SCByteSwap16(x) OSSwapInt16(x)
diff --git a/src/util-debug.h b/src/util-debug.h
index d3631fda2a..ec0309f636 100644
--- a/src/util-debug.h
+++ b/src/util-debug.h
@@ -29,7 +29,11 @@
 #include "util-error.h"
 #include "pcre.h"
 #include "util-debug-filters.h"
+#if defined __OpenBSD__
+//#include <sys/syslog.h>
+#else
 #include "syslog.h"
+#endif
 
 #ifndef __UTIL_DEBUG_H__
 #define __UTIL_DEBUG_H__
diff --git a/src/util-fmemopen.c b/src/util-fmemopen.c
index d6dfab1243..d551282368 100644
--- a/src/util-fmemopen.c
+++ b/src/util-fmemopen.c
@@ -33,6 +33,10 @@
 #define USE_FMEM_WRAPPER 1
 #endif
 
+#ifdef __OpenBSD__
+#define USE_FMEM_WRAPPER 1
+#endif
+
 #ifdef USE_FMEM_WRAPPER
 
 #ifdef OS_WIN32
diff --git a/src/util-fmemopen.h b/src/util-fmemopen.h
index 826a67db50..4b558eaf98 100644
--- a/src/util-fmemopen.h
+++ b/src/util-fmemopen.h
@@ -37,6 +37,10 @@
 #define USE_FMEM_WRAPPER 1
 #endif
 
+#ifdef __OpenBSD__
+#define USE_FMEM_WRAPPER 1
+#endif
+
 #ifdef OS_WIN32
 #define USE_FMEM_WRAPPER 1
 #endif
diff --git a/src/util-radix-tree.c b/src/util-radix-tree.c
index c43f15e485..00f678d0e2 100644
--- a/src/util-radix-tree.c
+++ b/src/util-radix-tree.c
@@ -30,7 +30,7 @@
 #include "suricata-common.h"
 
 #include "suricata-common.h"
-#ifdef OS_FREEBSD
+#if defined OS_FREEBSD || defined __OpenBSD__
 #include <netinet/in.h>
 #endif /* OS_FREEBSD */
 #ifdef OS_DARWIN
diff --git a/src/util-unittest-helper.c b/src/util-unittest-helper.c
index f7fbe01351..7906a056b8 100644
--- a/src/util-unittest-helper.c
+++ b/src/util-unittest-helper.c
@@ -24,9 +24,9 @@
  * when constructing unittests
  */
 
+#include "suricata-common.h"
 #include <netinet/in.h>
 
-#include "suricata-common.h"
 
 #include "decode.h"