The study was carried out to investigate the effectiveness of integrated and fragmented curriculum in development of basic skills at primary level. The main purpose of this study was to compare the relative effectiveness of integrated and fragmented curriculum in developing the basic skills of reading and writing at primary level. This was mixed method research in which both survey and experimental methods were used to achieve the objectives. Pretest posttest control group design was used to conduct the experimental study.First a survey was conducted to get the opinion of the teachers of primary education about current (fragmented) curriculum and the need of an integrated curriculum at primary level through a self developed questionnaire. The researcher developed integrated curriculum model for English by combining content of English and Social Studies and integrated curriculum model for Urdu by combining the content of Urdu and Islamiat by adopting multidisciplinary approach. While developing these models teachers'' opinion about integrated curriculum was given importance. Lesson plans were prepared by the researcher according to the model to teach the students of primary level. In order to measure the performance of the students'' teacher made achievement tests were prepared by the researcher. A try out of developed integrated curriculum model, lesson plans, teacher-made achievement test and questionnaire was taken in. The validity of the developed instrument was checked through expert opinion. This experimental work was carried out for sixteen weeks in Islamabad Model School I-9/4 Islamabad. Population of the survey study was the teachers of primary education of the schools of Islamabad city and the students of the class IV. Seventy six students were randomly selected from class IV for experiment. Students were assigned to experimental and control group after pre test. Experimental group was taught through integrated curriculum while control group was taught through traditional (fragmented) curriculum. After the completion of the experimental period post test was administered. The data collected through questionnaire and teacher made achievement was analyzed using SPSS and applying percentage method, Chi-Square, and t-test. In order to compare mean scores of experimental and control group independent sample t-tests was applied. Chi-Square was used to examine the association among different variables of the questionnaire and percentage method was applied to check the frequency of respondents. The results of study revealed that integrated curriculum was more effective in developing the basic skills of reading and writing in students at primary level as compare to the traditional fragmented curriculum. The study also revealed that teachers of primary education were familiar with the concept of integrated curriculum and they are strongly in favour of introducing integrated curriculum at primary level.