1. Register Analysis
In linguistics, a register is a variety of a language used for a particular purpose or in a particular social setting. Register analysis is an analysis of grammatical and lexical features of the language used for particular purpose or in particular social setting. This concept comes from the principle of ESP that English of a specific science differs from each other in terms of its grammatical and lexical features of the registers. By register analysis, the lecturer or teacher can produce a syllabus which gave high priority to the language forms students would meet in their Science studies and in turn would give low priority to forms they would not meet. Ewer and Hughes-Davies (1971), for example, compared the language of the texts their Science students had to read with the language of some widely used school textbooks. They found that the school textbooks neglected some of the language forms commonly found in Science texts, for example, compound nouns, passives, conditionals, anomalous finites, (i.e. modal verb). Their conclusion was that the ESP course should, therefore, give precedence to these forms.
  1. Rhetorical/ Discourse Analysis
In this stage, the second phase of development shifted attention to the level above the sentence, as ESP became closely involved with the emerging field of discourse or rhetorical analysis. It focuses to understand how sentence were combined in discourse to produce meaning. The concern of research, therefore, was to identify the organizational patterns in texts and to specify the linguistic means by which these patterns are signaled. These patterns would then form the syllabus of the ESP course. Stages of ESP development:
1.      First stage focused on language at the sentence level.
2.      Second phase shifted attention the level above the sentence (putting into play discourse or rhetorical analysis).
As in stage 1 there was a more or less tacit assumption in this approach that the rhetorical patterns of text organization differed significantly between specialist areas of use: the rhetorical structure of science text was regarded as different from that of commercial texts. The typical teaching materials based on the discourse approach taught students to recognize textual patterns and discourse markers mainly by means of text-diagramming exercises.
If we take this simple sentence: “I don’t have enough money”and we put it into two different dialogues, we can see how the meaning changes.
Do you want a cup of milk?
I don’t have enough money

Have you get lunch?
I don’t have enough money
  1. Target situation analysis
According to Hutchinson and Waters (1987), target situation analysis was aimed to take student’s existing knowledge and setting it on a more scientific basis by establishing procedures for relating language analysis more closely to learners’ reasons for learning. In ESP course, there will be a process of knowing students’ purpose to learn English known as need analysis or target situation analysis. Target situation analysis will lead the teacher to form a syllabus. John Munby in Communicative Syllabus Desig , produces a detailed profile of the learners’ need in term of communication purposes, communicative setting, the means of communication, language skills, functions, structures, etc.
  1. Skill and  Strategies
In this stage, we concern to the two thing, thinking process underlie language use and focus on underlying interpretative strategies. Some experts have made significant contributions to work on reading skill to describe about this process where the medium of instruction is the mother tongue but students need read a number of specialist texts which are available only in English.
The principal idea behind the skill centered approach is that underlying all language use there are common reasoning and interpreting processes, which, regardless of the surface forms, enable us to extract meaning from discourse.
The focus should rather be on the underlying interpretative strategies, which enable the learners to cope with the surface forms, for example guessing the meaning of words from context, using visual layout to determine the type of the text, exploiting cognates, (i.e. words which are similar in the mother tongue and the target language), etc. A focus on specific subject registers is unnecessary in this approach, because the underlying processes are not specific subject to any subject register.
  1. A Learning-Centred Approach
ESP concern with language learning rather than language use. The importance and the implications of the distinction that we have made between language use and language learning will hopefully become clear as we proceed through the following chapters. There are some main points that to be main focus in this stage:
· This is anyhow not the main concern of ESP since describing and exemplifying what people do with language will not automatically enable someone to learn it.
· Therefore, a valid approach to ESP must be based on an understanding of the processes of the language learning.