diff --git a/ir-parse.c b/ir-parse.c
index fa2a326..8eb75db 100644
--- a/ir-parse.c
+++ b/ir-parse.c
@@ -6,10 +6,89 @@
 
 #include <stdio.h>
 #include "json.h"
+#include "edk/Cper.h"
 #include "cper-parse.h"
+#include "cper-utils.h"
+
+//Private pre-declarations.
+void ir_header_to_cper(json_object* header_ir, EFI_COMMON_ERROR_RECORD_HEADER* header);
 
 //Converts the given JSON IR CPER representation into CPER binary format, piped to the provided file stream.
+//This function performs no validation of the IR against the CPER-JSON specification. For this, call
+//validate_schema() from json-schema.h before attempting to call this function. 
 void ir_to_cper(json_object* ir, FILE* out)
 {
+    //Create the CPER header.
+    EFI_COMMON_ERROR_RECORD_HEADER* header = (EFI_COMMON_ERROR_RECORD_HEADER*)calloc(1, sizeof(EFI_COMMON_ERROR_RECORD_HEADER));
+    ir_header_to_cper(json_object_object_get(ir, "header"), header);
+    fwrite(header, sizeof(EFI_COMMON_ERROR_RECORD_HEADER), 1, out);
+    
     //...
+
+    //Free all resources.
+    fflush(out);
+    free(header);
+}
+
+//Converts a CPER-JSON IR header to a CPER header structure.
+void ir_header_to_cper(json_object* header_ir, EFI_COMMON_ERROR_RECORD_HEADER* header)
+{
+    header->SignatureStart = 0x52455043; //CPER
+    printf("beginning write.\n");
+
+    //Revision.
+    json_object* revision = json_object_object_get(header_ir, "revision");
+    int minor = json_object_get_int(json_object_object_get(revision, "minor"));
+    int major = json_object_get_int(json_object_object_get(revision, "major"));
+    header->Revision = minor + (major << 8);
+
+    header->SignatureEnd = 0xFFFFFFFF;
+
+    //Section count.
+    int section_count = json_object_get_int(json_object_object_get(header_ir, "sectionCount"));
+    header->SectionCount = (UINT16)section_count;
+
+    //Error severity.
+    json_object* severity = json_object_object_get(header_ir, "severity");
+    header->ErrorSeverity = (UINT32)json_object_get_uint64(json_object_object_get(severity, "code"));
+
+    //Validation bits.
+    header->ValidationBits = ir_to_bitfield(json_object_object_get(header_ir, "validationBits"), 
+        3, CPER_HEADER_VALID_BITFIELD_NAMES);
+
+    //Record length.
+    header->RecordLength = (UINT32)json_object_get_uint64(json_object_object_get(header_ir, "recordLength"));
+
+    //Timestamp, if present.
+    printf("timestamp write.\n");
+    json_object* timestamp = json_object_object_get(header_ir, "timestamp");
+    if (timestamp != NULL) 
+    {
+        string_to_timestamp(&header->TimeStamp, json_object_get_string(timestamp));
+        header->TimeStamp.Flag = json_object_get_boolean(json_object_object_get(header_ir, "timestampIsPrecise"));
+    }
+
+    //Various GUIDs.
+    printf("guid write.\n");
+    json_object* platform_id = json_object_object_get(header_ir, "platformID");
+    json_object* partition_id = json_object_object_get(header_ir, "partitionID");
+    if (platform_id != NULL)
+        string_to_guid(&header->PlatformID, json_object_get_string(platform_id));
+    if (partition_id != NULL)
+        string_to_guid(&header->PartitionID, json_object_get_string(partition_id));
+    string_to_guid(&header->CreatorID, json_object_get_string(json_object_object_get(header_ir, "creatorID")));
+
+    //Notification type.
+    printf("notif type write.\n");
+    json_object* notification_type = json_object_object_get(header_ir, "notificationType");
+    string_to_guid(&header->NotificationType, json_object_get_string(json_object_object_get(notification_type, "guid")));
+
+    //Record ID, persistence info.
+    header->RecordID = json_object_get_uint64(json_object_object_get(header_ir, "recordID"));
+    header->PersistenceInfo = json_object_get_uint64(json_object_object_get(header_ir, "persistenceInfo"));
+
+    //Flags.
+    printf("flag write.\n");
+    json_object* flags = json_object_object_get(header_ir, "flags");
+    header->Flags = (UINT32)json_object_get_uint64(json_object_object_get(flags, "value"));
 }
\ No newline at end of file